The Use of Clay Pigments on Ceramic Vessel Sherds from the Hatchel Site (41BW3) and Comparisons to Ancestral East Texas Caddo Ceramic Vessel Assemblages

Repository Citation Perttula, Timothy K. (2017) "The Use of Clay Pigments on Ceramic Vessel Sherds from the Hatchel Site (41BW3) and Comparisons to Ancestral East Texas Caddo Ceramic Vessel Assemblages," Index of Texas Archaeology: Open Access Gray Literature from the Lone Star State: Vol. 2017 , Article 32. https://doi.org/ 10.21112/ita.2017.1.32 ISSN: 2475-9333 Available at: https://scholarworks.sfasu.edu/ita/vol2017/iss1/32

Introduction
The most distinctive material culture item of the Caddo groups living in East Texas were the ceramics they made for cooking, storage, and serving needs, and also included as necessary funerary goods. The styles and forms of ceramics found on sites in the region hint at the variety, temporal span, and geographic extent of a number of ancestral Caddo groups spread across the landscape. The diversity in decoration and shape in Caddo ceramics is substantial, both in the utility ware jars and bowls, as well to distinctive communities of identity and practice and the recognition of social networks from ceramic assemblages, where potters shared a group identity that can be reconstructed through the analysis of suites of technological and stylistic attributes (cf. Eckert et al. 2015:2).
Caddo potters made ceramics in a wide variety of vessel shapes, employing distinctive technological of well-crafted and executed body and rim designs and surface treatments. From the archaeological contexts in which Caddo ceramics have been found, as well as inferences about their manufacture and use, it is evident that ceramics were important to the Caddo in the cooking and serving of foods and beverages; in the storage of foodstuffs; as personal possessions; as beautiful works of art and craftsmanship (i.e., some vessels were clearly made to never be used in domestic contexts); and as social communities and constituent groups. Other motifs may have originally been more personal, perhaps deriving from body tattoo motifs.
polished surfaces, including bottles and many bowls of different forms, and utility wares with wet paste decorative elements (i.e., brushed, incised, punctated, etc.). These kinds of ceramics were designed to serve different purposes within Caddo communities and family groups-from that of a cooking pot both red (hatinu) and black (hadikuh commonly the vessels were then burnished and polished; red ochre and white (hakaayuh) kaolinite clay pigments were often added to the decorations on bottles and carinated bowls; green (hasahkuh) pigments have also been documented on some engraved vessels (see Fields and Gadus 2012: Table  6-3). Webb (1959:157) noted that a number of vessels at the Belcher site (16CD13) had a "pale green pigment…smeared irregularly on the surface of 15 burial vessels." The goals of this article are straightforward. First, I will examine the use of clay pigments in the site (41BW3) on the Red River in Bowie County, Texas (Perttula 2014(Perttula , 2015a (Figure 1), then discuss site. Finally, although not comprehensive (that effort still awaits), I consider the spatial and temporal diversity in clay pigment use among different Caddo sites and communities in East Texas.
Red and white clay pigments on ceramic vessel sherds are present in almost all of the different platform mound zones (Zones A-J) at the Hatchel site, and in the pre-mound habitation zone (Zone K). Based on the range of decorated sherds and vessels in the various zones, the pre-mound Zone K likely dates about ca. A.D. 1200, while the initial platform mound zones (I-J) date from ca. A.D. 1450-1500. Zones E-H likely date from ca. A.D. 1500-1600, and the latest platform mound zones (A-D) date from ca. A.D. 1600-1691. The Teran expedition of 1691 visited the Nasoni Caddo community on the Red River that includes the Hatchel site and mapped an earthen mound with a templo or temple structure on it that is believed to be the platform mound at the Hatchel site (Sabo 2012:438 and Figure 15-1).
There are 337 ceramic vessel sherds with either red (n=135), red and white (n=1), or white (n=201) clay pigments in the mound zones (Table 1). The pigments were used on bottles, carinated bowls, and compound bowls. By far the largest numbers of sherds with pigments are in zones G and H, but these zones also have the highest number of decorated sherds (Perttula 2014: Table 1). About 5.9 percent of the decorated sherds from Zone G have a clay pigment, compared to 9.4 percent in Zone H. In fact, the proportion of sherds with pigments in zones E-H is 7.3 percent, compared to 4.5 percent in zones below H-J, 2.9 percent in Zone K, and only 1.6 percent in zones A-D. The use of clay pigments by Caddo potters on ceramic vessels declined considerably after ca. A.D. 1600, after having peaked in use between ca. A.D. 1500-1600.
sherds are from deposits that cannot be associated with a zone in the platform mound. Five have red pigment and one has a white clay pigment. Bt=bottle; CB=carinated bowl; CPB=compound bowl The use of clay pigments by zone and temporal periods at the Hatchel site was not consistent, but changed through time. In the mound itself, by proportion, red pigments were most commonly used after ca. A.D. 1600, as 69 percent of the sherds with pigment had a red clay pigment (Table 2). In the earliest platform zones, dated ca. A.D. 1450-1500, about 53 percent of the sherds with pigment in the assemblages had a red clay pigment. Conversely, between ca. A.D. 1500-1600, sherds with a red clay pigment comprise only 36 percent of the assemblages; the one sherd with both red and clay pigments also occurred at this time. The use of a white kaolin clay pigment peaked between ca. A.D. 1500-1600, as 64 percent of the sherd sample with pigment had the white pigment smeared in the engraved lines (  (Table 3). The use of a white clay pigment on bottles was most common between ca. A.D. 1500-1600, as 21 percent of the bottle sherds with evidence of pigment use had a white clay pigment during this period. In the case of carinated bowls and compound bowls at the Hatchel site, a white clay pigment was more regularly used on these vessel forms. In the ca. A.D. 1450-1500 deposits, carinated bowls and compound bowls with a white pigment comprise 70 percent of the sherds from these vessel forms, compared to 76 percent of the sherds in the ca. A.D. 1500-1600 deposits, but only 37.5 percent of the sherds from these vessel forms in the ca. A.D. 1600-1691 mound zones (Table 3) Pigment use at the Belcher site (16CD13) on the Red River in northwestern Louisiana, contemporaneous with the use of the Hatchel platform mound, was also extensive. More than 63 percent of the 116 engraved ceramic vessels in the Belcher phase component at the site had pigments in the engraved lines (Webb 1959:157). Webb noted a correlation between vessel forms, ceramic types, and use of either white or red pigment. Carinated bowls of the Belcher Engraved type had white pigment (as they commonly did at the Hatchel site), while bottles of the Hodges Engraved type had red pigment. In the vessel assemblage as a whole, 36 engraved bottles and bowls had red pigment, while 37 bowls and For comparative purposes, I compiled information on the use of clay pigments in several Early Caddo, Middle Caddo, Late Caddo, and Historic Caddo period ceramic vessel assemblages in East Texas; many other assemblages warrant study for clay pigment use, but this research awaits completion. This includes the Middle Caddo period Washington Square Mound and Sanders sites (Perttula et al. 2010(Perttula et al. , 2016; the Pine Tree Mound and Mockingbird Late Caddo, Titus phase, sites (Fields and Gadus 2012;Perttula et al. 1998), Late Caddo Frankston phase vessels from the upper Neches River basin (Perttula 2011); and Historic Caddo About 27 percent of the engraved vessels from Early Caddo period features at the George C. Davis site (41CE19) on the Neches River have clay pigments rubbed in engraved decorative elements. Of these vessels, 86 percent have a red clay pigment; the red pigment was clearly preferred by the Caddo potters at the George C. Davis site, particularly on Holly Fine Engraved vessels (Perttula 2016). The red clay pigment was added to one Hickory Engraved jar, two Holly Fine Engraved bottles, two Holly Fine Engraved bowls, and one Holly Fine Engraved carinated bowl. The one vessel with a white clay pigment in the assemblage is a Holly Fine Engraved bottle.
In the case of the Middle Caddo period vessel assemblages, about 21 percent of the engraved vessels at each site had a clay pigment rubbed in the engraved lines. Between 60-75 percent of these vessels have a red pigment (Table 4). At the Washington Square site, bottles and carinated bowls have red pigment, while the white pigment was applied to the engraved lines of two compound bowls (Perttula et al. 2010). Carinated bowls and bowls at the Sanders site have a red clay pigment, and one carinated bowl has a white clay pigment (Perttula et al. 2016 ___________________________________________________________________________ percent of the engraved vessels had an applied pigment (Fields and Gadus 2012: Table 6-3). Although pigment use was rather equally spread between the red and white clay pigments in the vessel assemblage, unlike the other assemblages discussed in the text except for the ca. A.D. 1450-1500 deposits at the Hatchel platform mound (see Tables 2-3), almost all the bottles (86 percent) had a red clay pigment, while 86 percent of the carinated bowls and 89 percent of the compound bowls had the white clay pigment, one of the highest proportion of white clay pigment use in these vessel forms in the East Texas ceramic assemblages under consideration herein. The only higher percentage of white clay pigment use is in the Mockingbird site vessel assemblage (see Table 4). There, 95 percent of the engraved vessels with pigments have a white clay pigment, including all of the carinated bowls (n=12), compound bowls (n=5), one bottle, and one bowl; another bowl had a red clay pigment (Perttula et al. 1998). Forty-three percent of the engraved vessels in the assemblage have a pigment applied to the decorative elements.
Other Late Caddo period Titus phase vessel assemblages in the Little and Big Cypress Creek basins in East Texas are dominated by vessels with white clay pigment, especially on carinated bowls and compound bowls as well as jars; bottles mainly have red clay pigments (Perttula et al. 2012a(Perttula et al. , 2012b(Perttula et al. , 2012c. Bowls in these assemblages, which rarely have pigments, have both red and white pigments; ollas tended not to have an applied pigment of either color (Perttula et al. 2012a:35).
In the upper Neches River basin, by contrast, a temporal series of Late Caddo Frankston phase vessels with pigment have a red clay pigment, and instead use of a white clay pigment predominates; most of these vessels are carinated bowls (Perttula 2011:279-280).
In the Historic Caddo vessel assemblages from the nearby Goode Hunt and Clements site, both ca. ranges from 25-29 percent of the sample of engraved vessels. Eighty percent of these vessels have a red clay pigment, and this includes bottles (n=4, 100 percent), bowls and compound bowls (n=2, 100 percent), and carinated bowls (n=9, 67 percent). Only a few carinated bowls in the vessel assemblages at both sites have a white clay pigment.

Summary and Conclusions
Ancestral Caddo potters in sites and communities in what is now East Texas used clay pigments, ware vessels suggests that both red and white clay pigments were readily accessible to Caddo potters in communities across East Texas and surrounding locales, and it is likely that there was an active trade/ exchange of pigments across the region that were secured from sources of hematite and kaolin clay. assemblages in the region (from ca. A.D. 1000-1730), indicate that there were spatial and temporal differences in the frequency of use of clay pigments by Caddo potters as well as in the pigments of choice to use on different vessel forms. The assemblages examined to date indicate that there was not one shared pattern or tradition in pigment use within sites occupied at different times or within different localities, although the use of red clay pigment appears to have been more common between ca. A.D. 1000-1400. Rather there was a diversity in pigment selection and use that is probably related to the meaning(s) of the two colors in different Caddo communities, and what the meanings were in different times and places. Lankford (1992) discussed the importance of the use of either red or white colors in social, political, and cosmological contexts in Southeastern North American societies, and such contexts likely also apply to ancestral Caddo groups that lived in East Texas. As Hart and Perttula (2010:208) note, colors likely "symbolize the cosmological underpinnings of worldviews." According to Bobby Gonzalez (April 2008 personal communication) "the red pigment means life and is very sacred among the Caddo. The red pigment is now used on peyote staffs, and during ritual ceremonies and prayer meetings, the red pigment is painted on and in the ears as well as on the top of the head in the middle of a man's hair line, running from front to back; the women and men paint themselves in the morning when the sun comes up." Caddo peoples bathed the deceased in red clay (Gonzalez 2005:57), and in historic times red was used as a paint or pigments on material items in ceremonies (Hart and Perttula 2010:208). Red ochre is readily associated with blood and life (Miller 2015:61). Therefore, vessels with a red pigment likely are from vessels that symbolize life and its sacredness to the Caddo. It is possible that the red pigment seen on vessels placed in Caddo burials may have been added to the vessels shortly before they were placed in graves with the deceased.
"The white clay is also very sacred to the Caddo and was used for altars during Caddo peyote meetings" (Bobby Gonzalez, 2008 personal communication), and for doctoring cuts, burns, and stomach problems. In historic times, Caddo men painted their faces red and white, and white feathers were a sign of peace (Hart and Perttula 2010:208).
In conclusion, the alternating preference for red or white clay pigments by Caddo potters in different communities at different times may relate to social, political, or religious dualisms in Caddo lifeways. Thus, Lankford's (1992:76-77) suggestion that the two colors denote the Lower world of change (red) on ceramic vessels by Caddo peoples. Before ca. A.D. 1400, between ca. A.D. 1400-1560 in the upper Neches, and between ca. A.D. 1680-1730 among the Nasoni Caddo, red clay pigments appear to have world views of the Caddo began to change in certain communities in East Texas after ca. A.D. 1400, such that new cosmological and world views came to dominate beliefs and mortuary ritual use; one marker of this is different trends in pigment use. Fine ware engraved vessels in a number of mortuary vessel assemblages dating after ca. A.D. 1450 usually then had white pigments rubbed in the design. Finally, George Sabo has noted that color use by Caddo peoples "suggest an association of red and white with an ongoing cycle of life in which birth and death are subsumed" (May 2009 personal communication).
Thanks to Chase Earles and Duncan McKinnon for comments on the manuscript. Thanks also to Tom Middlebrook for the discussion concerning pigment use by Caddo potters in East Texas.


THE VAST PROJECT: VALORISATION OF HISTORY AND LANDSCAPE FOR PROMOTING THE MEMORY OF WWI

: The VAST (valorisation of history and landscape) project (http://vast.fbk.eu/) was part of the initiatives promoted by the Autonomous Province of Trento (Italy) for the commemoration of the 100th Anniversary of the First World War (WWI) outbreak. The project was

. (a) Positions of the Austro-Hungarian forts along the old national border (before 1918) between Italy and the Austro -Hungarian empirenowadays a regional border between T rentino -Alto Adige and Veneto (b) An historical picture showing the plateaus and highlands 'Altipiani Cimbri'. (c) Vezzena fort as it appears today and (d) its virtual reconstruction.

INTRODUCTION
VAST (valorizzazione storia e territorio/valorisation of history and landscape) was an interdisciplinary project, run from June 2013 to June 2015 with the ambition of exploiting current 3D modelling and visualization technologies to reinforce and enrich with new significance the heritage sites and monuments on the mountainous area in the North East of Italy related to the Great War. 3D digital models, virtual tours and WebGIS were produced to document, communicate and valorise military fortresses, war objects and the entire landscape of the Altipiani Cimbri, i.e. the plateaus and highlands of Luserna, Lavarone and Folgaria (Trento province, Italy). The project was scientifically coordinated by FBK-3DOM and run in collaboration with various partners and local stakeholders, with complementary expertise in cultural and technical research field to reach the goals of digitizing and communicating the WWI heritage and memory for the commemoration of the 100th Anniversary of the war outbreak. Different researchers, now working for other institutions, took part in project activities. Compared to previous publications showing partial results of the VAST project, this paper aims at summarising all the relevant results achieved within the project and follow-up activities, emphasizing the social, cultural and educational values of the presented research.

Background and motivation
The area under investigation was part of the Austro-Hungarian Empire until the end of the First War World (WWI) and represented one of the crucial border with the Italian kingdom ( Figure 1a). Consequently, the territory was constellated of military fortresses, trenches and underground tunnels (Section 1.2) that represent a unique heritage patrimony, especially for the Altipiani Cimbri (Figure 1b), an area lived by an ethnic and linguistic minority, the Cimbrians, a population descending from German people and speaking Cimbrian, a dialect of Bavarian that has maintained characteristics of M iddle High German (Coluzzi, 2004). The Cimbrians are one of the minorities protected by Italian State Law since 1999 and nowadays they live in four different areas in the North-East region of Italy, one of them being the plateau of Lavarone, Folgaria and Luserna. The VAST project was strongly supported by members of the Cimbrian community, persuaded that the new digital technologies would have helped in the valorisation and preservation of their cultural heritage. M ost of the military constructions are now ruined ( Figure 1c) and risk to slowly disappear. To reach the primary goal of enhancing the conscience of what the war had represented for the local community, in particular for the young generations that have not directly witnessed its cruelty, 3D military structures and objects were surveyed and modelled, producing new dissemination and communication materials, displayed both in museums and along the main routes running across the Altipiani Cimbri territory. The realized products comprise both classic informative posters, mainly devoted for an adult audience, and virtual and interactive reconstructions of war buildings, objects and landscape, more appropriate for the young generations.

The Austro-Hungarian forts in Trentino
In the XIX century, the Trentino -Alto Adige was the last Italian territory still belonging to the Austro-Hungarian Empire.
Aiming at protecting it against the spread of the Italian unification movement, more than 50 military fortifications, or werk in German, were built. In particular, a double set of fortifications organised in an internal and external ring were erected to protect the city of Trento, capital of the Trentino province (Cacciaguerra & Gatti, 2010). From the 1830s to the WWI outbreak, four generations of forts, corresponding to six different construction phases, were designed and built, each of them at different heights on the mountains: • the 1st generation (first three phases) comprises forts situated at the entrance of the valleys, as a natural bottlenecks and block of the main routes • the 2nd generation (beginning of 1880) features fortifications at higher altitude, characterized by a simple planning scheme known as "Trentino style" • the 3rd generation, called "Vogl era", was built to complete the defence belt of the eastern Trentino front and consists of armoured forts, fitted with reinforced domes and shields for the artillery in the casemate • the 4th generation (1904)(1905)(1906)(1907)(1908)(1909)(1910)(1911)(1912)(1913)(1914) was promoted by the Austro-Hungarian general Conrad von Hötzendorf and is characterised by fortresses made in concrete and steel located on the plateau and on the top of mountains. The fortresses realized on the Altipiani Cimbri and main subjects of the VAST project belong to the 4th generation. Each fortification, with casemate, rotating domes, corridors and underground passageways to smaller reinforced blocks, was often realized with their main body completely carved in the rock in order to be camouflaged and so that only the façade was visible from outside.

DIGITAL DOCUMENTATION OF CULTURAL HERITAGE THROUGH DIFFERENT DATA S OURCES
In the last years, digital 3D modelling and visualization techniques have been widely employed to document sites of cultural significance, as well as patrimony threatened by both human (war, mass tourism, pollution) and natural (flooding, sea water rising, earthquakes) influences. Digital reconstruction implies the representation of the artefact or monument to its original state (Georgopoulos, 2014) and requires the verification of the suggested reconstruction through additional information, such as historical documents, images, records. In Kinji et al. (2008), for example, the app roach to 3D modelling of buildings of the Citadel of Bam, a UNESCO world heritage site destroyed after an earthquake, is discussed. Complementary data, such as 2D maps, photos, maps, are used to provide a digital restoration of the site. Examples of multidata source and multi-sensor approaches are discussed in Guidi et al. (2009), Remondino et al. (2011), andTorres-M artínez et al. (2015. Guidi et al. (2013) and Hanke et al. (2015) integrated 3D data with historical sources. Digital documentation of archaeological sites at risk and digital restoration of lost cultural heritage using photogrammetry and crowdsourced images are the aims of the Rekrei (https://projectmosul.org/, Vincent et al., 2015) and Curious Travellers (http://www.visualisingheritage.org/CT.php ) projects. Records of travellers in the 17 th and 18 th were used as basis for the reconstruction of destroyed heritage site of Palmyra (Denker, 2016).

WWI commemoration projects
All around the World, the centenary commemoration of the Great War outbreak has been recognised as key moment, not only to honour who sacrificed their lives in the war, but also to understand the influences of those events on our society, and convey their memories to young generations. Besides a number of national and local events, ceremonies, and exhibitions, also international organizations have promoted several initiatives. For example, Europeana, the European digital platform for cultural heritage, has sponsored three digital projects: Collections 1914Collections -1918Collections ' (http://www.europeana-collections-1914Collections -1918 , was a collaboration involving both academic and non-academic experts in different disciplines with the aim of collecting and sharing multi-media contents and providing it through thematic collections that could be used for innovative teaching approaches and studies, verification of hypothesis and theories, revision of the War itself in its social, cultural, historical and political context. Digital techniques were also employed to virtually simulate the underground warfare using Unity 3D (Lindsay, 2013). Another project designed to share online cultural heritage collection related to the Great War is t he 'World War I Memorial Inventory Project' (http://ww1mproject.org/). The website is a searchable database of U.S. WWI memorials, that includes images, history, state of conservation, the names of veterans. 3D models, created employing photogrammetry, are also available in a 3D web viewer based on Sketchfab (https://sketchfab.com/). As further proof that the Great War represents a milestone in the history of Trentino, it is worth mentioning the 'World War I 1914War I -1918 Trentino, Italy, Europe' project (http://isig.fbk.eu/projects/world-war-i-1914-1918-trentinoitaly-europe). Its main aim was to deepen cultural and social history of the war at different scales, from the Trentino territory up to the broader European context.

PROJECT BACKGROUND AND IMPLEMENTATION
The research activities realized within the VAST project were mainly focused on the identification of innovative, affordable and reliable methods for the virtual reconstruction of valuable symbols of the Great War in the Altipiani Cimbri territory. Three-dimensional (3D) models of fortifications and war objects were realized using 3D surveying and modelling techniques. Immersive virtual tours (VTs) based on panoramic images were produced to allow, also remotely, a fascinating way of travelling and visiting the war space, making it possible to understand the connections between sites geographically far away from each other. The main war events, like the war front localization or trenches position, were collected in a geographic information system accessible online (WebGIS), in order to enrich the geography of the territory with historic memory.

3D surveying and modelling of war scenarios and artefacts
The 3D modelling procedure developed and adopted for the surveying and modelling of the forts and underground passages has been presented in two previous publications (Nocerino et al., 2014;Rodríguez-Gonzálvez et al., 2015). Here, the salient aspects of the developed procedure are summarised in the next sections.
Great efforts have been devoted in the modelling of the Austrian-Hungarian forts disseminated over the Altipiani Cimbri territory. Indeed, nowadays the majority of the WWI forts in the Trentino region are ruined, both for the damages naturally induced by the war hostilities and also because during the Fascism period, the iron in the military buildings (mainly the beams) was removed to be reused. Integration of the produced 3D model into the digital surface model for visualization purposes.

S tudy and digitization of historic documents:
A scrupulous literature review was carried out in order to identify the original construction drawings of the Austro-Hungarians fortifications (Figure 2a). The drawings were digitized through the procedure described in detail in Nocerino et al. (2014) and here briefly recalled. For each available historical drawing, a close range photogrammetric survey was realised in order to produce orthoimages of the drawings. A typical photogrammetric network (Figure 2b) acquired with a calibrated SLR camera is processed with a fully automatic orientation, dense image matching and mesh procedure. The orthophoto was finally generated. The accuracy of the proposed methodology for orthophoto production was assessed through comparisons with traditional rectification methods, both analytical and geometrical. The results showed that the adopted photogrammetric-based approach was generally comparable with the classical procedure, with the advantage of being fully automated and independent from the operator precision. However, when the historical drawings displayed big deformation, all rectification methods produced differences greater than the plotting accuracy. Other historic sources of information were also collected and digitized: antique maps, war front position during the years of conflict, localization of cableways position and trenches. The digitised documents were collected in the WebGIS application (Section 3.3). The digitized construction drawings (Figure 2c) were used as basis for the 3D modelling procedure (Section 3.1.3).

3.1.2
Data acquisition on site: Terrestrial and drone/UAV ( Figure 3a) photogrammetric surveys, integrated with terrestrial laser scanning acquisitions (Figure 3b), were conducted to digitally record and then measure the actual situation of the forts on the Altipiani Cimbri. The photogrammetric and laser scanning surveys were realized mainly to: (i) obtain reference measurements (for example, height and length of the façades, number and position of the windows), (ii) select the design project plans actually used to build the forts, (iii) verify the correctness of historical designs used in the later stages of modelling, (iv) integrate the missing design data and (v) geo-locate the fortifications. The surveying operations were usually concentrated on external and visible part of the structures as most of the interior/indoor parts are in danger and accesses are normally forbidden. An ad-hoc procedure for surveying and modelling of underground passages, not suitable for classic measuring approached, was also developed and is described in details in a second scientific work also presented at an international conference . Concisely, a dense point cloud of the underground structured was acquired using terrestrial laser scanner -TLS (for the geometry) and images (for colour information). The simplification approach aimed at developing a systematic procedure allowing the traceability of the whole process and avoiding subjective interpretation in the modelling process. The method, based on free software applications, involved a two-step procedure: (i) a high spatial resolution mesh generated with Poisson algorithm (Kazhdan and Hoppe, 2013) implemented in CloudCompare version 2015 (http://www.cloudcompare.org/) from the input point cloud, and (ii) a successive iterative geometric optimization based on the quadratic edge collapse algorithm (Garland and Heckbert, 1997) implemented in M eshLab (Cignoni et al., 2008). This last step is repeated iteratively: the mesh derived from the previous step is 'collapsed' of 5% of total number of triangles until the resulted mesh error against the original input point cloud remained within a user defined threshold. For the VAST project, considering the scale of the original drawings (1:50 up to 1:800), a common drawing error of 0.25 mm, and additional source of errors due to paper deteriorations and digitization error, a final spatial resolution of about 12 cm and a standard deviation of 0.8 cm from the original, full resolution point cloud was considered adequate. Following the described procedure an 87% reduction of the triangles, preserving significant geometric information, was obtained for the 110 m long underground tunnel, part of the Luserna military fortification (Figure 4). 3D models of forts: The original design drawings (plants, original digitized sections and / or tables), digitized according to the procedure described in section 3.1.1, were used as basis for the 3D modelling procedure. Classic CAAD (computer aided architectural design) modelling tools (e.g. extrusion, Boolean operations of solids) have been applied to produce digital models of the forts. Geometrical information extracted from longitudinal and cross sections, elevations, have been employed to extrude the original height and position of the different floors. Similarly, 3D solids of domes and roofs were created from 2D polylines and curves, derived from the available design drawings. 3D models representing the geometry of the buildings were then enriched with a texture mapping process: virtual textures were created on the basis of information from existing forts of the same period that have been already restored and historical images ( Figure 5).

3.1.4
3D modelling of war findings: On the plateaus of Luserna, Folgaria Lavarone several items used by the Austrian and Italian troops during the Great War have been found. These artefacts are now preserved and displayed at the Centro Documentazione museum in Luserna, and were digitized with 3D fringe projection scanning and photogrammetric techniques ( Figure 6).

S haring the 3D models:
The realised 3D models of both forts and war findings have been shared both on the Europeana portal (http://www.europeana.eu/portal/en) within the '3D Icons project (http://3dicons-project.eu/) funded by the European Union and on the 3DOM 3D models repository (http://3dom.fbk.eu/repository/portal/portal.html). Each model is interactively visible in a javascript-base web viewer (https://code.google.com/archive/p/jsc3d/) embedded in a dedicated web page (Figure 7), where all the relevant information (metadata, description of the surveying and modelling technique) are shown.

Virtual tour of the war territory
With the same perspective of enhancing the cultural value of the symbols of the Great War by increasing their visibility and accessibility, a virtual tour consisting in immersive panoramic images showing the Altipiani landscape, as well as the actual situation of the forts and military structures, was realised and made available on line (http://3dom.fbk.eu/repository/files/vast/vt/tour.html).

WebGIS
In order to make available all the "geographic" data collected, heterogeneous both for type and "provenance" (publications, measurements on site, etc.), a geographic information system accessible online (WebGIS, http://vast-gis.fbk.eu/) was realized. The base of the WebGis is a database, consisting of tables where the different available data were collected and organized. For example, the table related to the forts contains various information such as theirs names, construction details, or the type of armament. The web interface allows the user to view the information of interest (for example, location of the border at the beginning of the conflict) due to implemented functions (query) that "interrogate" the database to extract the required data and display it.

FOLLOW-UP OF THE PROJECT
The VAST project had various follow-up activities based on its products and achievements.

The Trento Citta' Fortezza project
The Trento Citta' Fortezza (Trento City Fortress, http://trentocittafortezza.fbk.eu/home) project was started in t he beginning of 2016 in cooperation with a high school (Istituto Buonarroti -Pozzo, http://www.ittpozzo.it/) in Trento. T he aim of the project was to actively involve young students in the creation of cartographic and multimedia products related to the city of Trento during the WWI. The city was fortified by the Austro-Hungarian army at the beginning of 1900 to defend its territory from any Italian military assault. The main objectives of the projects were to: • collect heterogeneous data regarding the Fortress of Trento in the WWI; • survey and model the Austro-Hungarian military structures in the area of Trento, included the fortifications on M onte Celva (Figure 8a, http://3dom.fbk.eu/repository/3Dpointclouds/celva/in dex.html); • realize end-products such as paper maps, WebGIS (Figure 8b, http://3dom.fbk.eu/repository/files/ITT/ gistcf.html) and Apps for mobile devices.

3D survey for restoration purposes of Sommo Alto fort
In June 2016, the public administration of the municipality of Folgaria (Trento) engaged the FBK-3DOM group, that led the scientific and technological activities of the VAST project, to survey and model the Sommo Alto fortification. The commitment consisted in producing 2D sections and plans of the Sommo Alto fort for planning the restoration of the internal structures of the military building. 2D drawings at 1:50 scale were extracted from a very dense point cloud of the fortification (Figure 9), acquired using an innovative hand-held mobile indoor 3D mapping system (http://geoslam.com/). The final segmented 3D point cloud of the fort is accessible on-line (http://3dom.fbk.eu/repository/3Dpointclouds/index.html#fortes ommoalto).

CONCLUS IONS
The VAST project has provided a timeless rebirth to the memory of the Great War in the area of Trento. 3D digital models of the original appearance of military fortresses were realized, based on historic evidences (maps and photos) and measurements acquired on site. Analogously, military objects found on the plateaus and now stored in the museums were digitized. All 3D models are made available on the web, to allow their access also with smart devices directly on site. Immersive virtual tours, communication material and WebGIS were realized too. The first, based on panoramic images, allow to travel and visit the war space ("warscape"), understand connections and links in a virtual and unique way. Communication material, based on 3D reconstructed scenarios and objects, allow to disseminate cultural information and reach also young generations. The WebGIS displays the main war events and localizations such as fortification and trenches, positions, in order to enrich the geography of the territory with historic memory. The WWI places and items have been enriched and empowered with new meaning thanks to the exploitation of 3D digital technologies. The possibility to access 3D digital models almost everywhere, even on trekking paths on high peaks, allows also non experts in understanding better and deeper the history and culture of the territory . And this is even truer when it comes to the Austro-Hungarian forts now in ruins. Thanks to the VAST project, young generations can now "see" and, then, really understand what their complex and impressive structure should have been. Scientists and researchers can verify their own hypothesis and theories, make comparisons with buildings or war objects of other historic periods or present in other geographic and cultural areas.
The results of the VAST project are expected to promote touristic and cultural richness of the Altipiani Cimbri, mainly through their on-line (web) and on-site (thanks to wireless network communication) accessibility. The 3D digital models may be included in further products, like augmented or virtual reality (AR/VR) applications, serious games for education and awareness-raising, etc.


Love Letters – Wearing Stories Told: A performance-technology provocation for interactive storytelling

This article focuses upon artistic modalities for the dissemination of personal and intimate memories to examine the relationship between technology, performance and audience. Drawing upon theoretical frameworks from social science and performance studies, sound art and computer science, the discussion is contextualised by combining three different perspectives. In doing so, the article concentrates on the authors’ collaborative and ongoing performance project Love Letters. The piece invited the participating audiences to write letters that capture platonic, familial or lustful emotion; share other audiences’ letters and interact with the performer’s costume by attaching the letters to her dress in addition to documenting names, memories, and streams of consciousness to the costume and onto the performer’s body. Love Letters was recently augmented with creative technologies and redeveloped as an interactive sound installation that’s both content and curation is user-generative. Through contextualising the performance project, this article investigates the different types of interfaces used in the performance (considering both their cultural and biological significance): body, skin and dress, which have been used to communicate written narrative. Viewing the project from a ubiquitous computing standpoint, we focus on the role of technology in such a setting. However, the primary importance is not the technology in itself but the pervasive effect it has on the storytelling process. Through our case study we propose how pervasive technology can support reminiscing and facilitate a sustainability in performative settings such as storytelling practices, while not drawing attention away from the performative and storytelling aspects of the piece.

Introduction
Love Letters is an ongoing performance project initially conceived by live art practitioner and academic Yiota Demetriou. It combines aesthetics of performance and sound art/installation. The work involves sharing private memories, exhibiting public histories, and uses audience participation and the act of storytelling. The original form of the piece invited audience members to write anonymous love letters to a significant other using the four types of Greek love: 1 Agape, Eros, Filia, Storge. In turn, the audience selected and read aloud other audiences' love letters (from the bank of letters collected from each performance); they inscribed the name of the sender and the addressee on the performer's dress and/or body and furthermore pinned the narrated letter onto the dress. From being re-performed, 2 the current love letters collection holds more than 200 audience letters. Past audiences' letters are re-activated in each performance, and new love letters are written and added to the collection (See Figures 1 and 2).
Love Letters was recently augmented with creative technologies and redeveloped as an interactive sound installation, the content and curation of which is usergenerative. This piece is used as a primary case study to address the uses of ubiquitous computing and wearable technology in performance, to make personal histories exchangeable and accessible. Through contextualising the performance project, this article 3 investigates the different types of interfaces used in the performance (considering both their cultural and biological significance): body, skin and dress, which have been used to communicate written narrative. Viewing the project from a ubiquitous computing standpoint, we focus on the role of technology in such a setting. However, the primary importance is not the technology in itself but the pervasive effect it has on the storytelling process. Through our case study we propose how pervasive technology can support reminiscing and facilitate a sustainability in performative settings such as storytelling practices, while not drawing attention away from the performative and storytelling aspects of the piece.

The Dress as Interface
Love Letter's symbolic actions do not only intervene in the notion of 'keeping' private memories by compelling the audience to participate in an exchange of them, but also by further witnessing others. This is realised by 'exposing' their intimate and personal testimonies (with their consent). Psychologist Jerome Bruner reasoned that narrative is a cultural mediator that 'mediates between the canonical world of culture and the more idiosyncratic world of beliefs, desires and hopes ' (1990: 52). If this is indeed the case, then the stories written and told in Love Letters -even though they do not have a collective or empirical significance, still make evident how narrative is a vital component of the human mind, key to making sense of the world around us. In light of this, the collected works are types of candid cultural artefacts or resources that carry 'intangible' personal heritage. As Barthes suggested: 'the special dialectic of the love letter, both blank (encoded) and expressive (charged with longing to signify desire) ' (1977: 157), tell stories that are sometimes profound and intense, and at other times superficial and trivial, which are then given existence through their mediation.
The action of writing a letter was used as a tool to evoke memories. The different sets of praxis undertaken during the performance in Love Letters intervene further in the idea of 'keeping' private remembrances to oneself. This is achieved by by having the audience engage with the performer by dressing her in particular ways so that the shared memories become attached with new environments, connotations and other ways of telling. These modes of engagement occur through two strands of audience -performer interaction: (1) writing the letter and reading another aloud (see Figure 3), or (2) pinning the narrated letter onto the dress and writing on the dress and on the performer's body. The second additional layer comprises of addressee names, memories, notes, streams of consciousness, a sentence, or a word (specifically on the theme of love), which capture an experience of platonic, familial or lustful emotion by inviting the audience to document these on the performer's body. The dress worn in every performance is the same. It is 'stained' with past and present audiences' contributions, playing with the notions of presence and absence. As described, the audience would note the name of the sender and the addressee on the garment and or the performer's body. Additionally, the dress also contains 'memo'-type messages that people left on it, for others to see and perhaps to not see. Thus, the dress is a crucial component of the performance. It becomes part of the audiences' recollections, not only as given traces of past written and narrative acts, but also as an in-between, a mediator, of what was said and what was lost. It most importantly becomes a vessel that embodies these people's intimate stories. In this sense, the dress witnesses the different tellings and shares a different type of intimacy with each and every audience member that has interacted with it. It is a technology that is physically embedded with their memories, as well as the cultural connotations it carries because of its material form. Theorists such as Nikolai Trubetzkoy (1939), Roland Barthes (1957), and Umberto Eco (1986) understood the generic sense of 'dress' as a form of technology taking into account both its material and conceptual values: a semiotic device and machine for communication. Another approach to viewing clothing as a type of technology, which links to the idea above in terms of its sociological significance, is through an Aristotelian lens, whereby technology is thought of as an external object, a tool for the human, 'that promises us pleasure' (Kember;Zylinska, 2009: 8). For Sociologist Read Bain (1937) 'technology includes all tools, machines, utensils, weapons, instruments, housing, clothing, communicating and transporting devices and the skills by which we produce and use them'. This idea can be related to Bernard Stiegler's (1994) work.
Grounding his theories on the works of Gilbert Simondon (1958), Stiegler defines technology in two ways: as 'the pursuit of life by means other than life', and as 'organised inorganic matter'. For him technology can be defined as both material and immaterial entities, which are produced through applying mental and physical labour towards attaining value (1994). Following this train of thought, for both Simondon and Stiegler the human and the technical are co-constituted. This state of Technocity, as Stiegler coins, suggests that technology is constitutive and simultaneously a supplement of the 'human', for the reason that the contemporary comprehension of the experience of being human and what is understood as technology are reciprocally co-constituted. Marshall McLuhan also wrote about this in his chapter Clothing: Our Extended Skin, suggesting that western civilization moved towards an ideology of 'postindustrialism', which views clothing as a technology that is a 'direct extension of the outer surface of the body ' (1966: 163). Thus, by having the audience pin the letters, it simultaneously works as a platform to exhibit these different stories and experiences, embodying the audience members' personal stories that were shared during each performance. As Susan Elizabeth Ryan maintains: Interfacing is a traditional sartorial term for an internal layer of stiffened fabric that supplies body and shape and helps edges lay straight. Technology adds physical and behavioural layers and can further articulate, or give shape to, its role in constructing the body and its subjectivity (2014: 134).
Hence, if the skin is a surface, then a dress adds layers to the body and becomes an embodied cultural interface performing a type of speech-act or performative utterance between ourselves and our environments (Ryan, 2014: 134, 140). Since the Futurist movement, artists have used dress in performance to provoke a social critique. An existing example of a technology-based performance work that used the idea of 'dress', is Electric Dress or Electric Clothes (1956) by Gutai artist Atsuko Tanaka, which culminated in a series of electrically wired clothing pieces. The main piece consisted of a kimono made of electrical wiring and diversely shaped and coloured fluorescent bulbs, which flashed on and off in a casual pattern scheme. When Tanaka wore the robe, it projected 'a visuality of a body transforming itself in quick succession […] a body which alters minute by minute' (Ryan, 2014: 17). Initially the artist performed the dress itself, as a dress act, seeing that it formed a flux in the space between art, technology and the body. The artist would wear it and perform in it, in terms of thinking about the costume as a sculpture. Tanaka's piece dealt with intangible features such as electricity and sound, and a certain automatism that was inspired by the different industrial mechanical workings of her time (Butler, de Zegher, 2010: 167). The artist enacted her body by using the format of the dress as its main interface with technology. As Susan Elizabeth Ryan suggests the dress 'was a means to "speak technology" -not merely to covertly enhance a function but to use technology as a communicative action ' (2014: 50). For further development of the project the dress used in Love Letters has been thought of as a type of interface that connects present and absent audiences. Jennifer Sheridan et al. write that the purpose of technology is to mediate the interaction and interfacing between the people involved in a performance and the performance itself. In this role, technology can support the integration of performers, participants and observers into the performance (in Fincher, et al., 2004: 7).
Using a 'gedankenexperiment' approach, the dress from Love Letters has been reworked in collaboration with Electronics/Signals Engineer Odysseas Pappas and Composer/Sonic Artist Stathis Kampylis, as an interface to examine the relationship between participation, technology and performance. Using creative technologies, the Love Letters dress has been redeveloped into a freestanding interactive sound installation, which is augmented with recordings of the letters from the existing collection. Audience members are invited to follow the initial process of writing a letter and engage with the dress and the performer by reading another letter from the collection and pinning it onto the dress. The audience's engagement with the garment triggers a reaction where the costume narrates another story from the love letters collection. Recordings of the collected letters are played via a sensory interface that is crafted onto the dress, and which has mini-speakers as outputs. The stories are held on a modular microcontroller. Triggered by the audiences pinning the letters onto the dress, it reacts by feeding back a different story from the Love Letters' database to the audience. In this way, the dress becomes a storytelling object and facilitates a two-way exchange of personal testimony: the garment becomes a listener/witness to the story being told by the audience member, but it also becomes the storyteller. Simultaneously, this shift of roles also happens to the audience members.
The audiences' engagement in the work was active even before augmenting technologies onto the dress, as the content was 'user-generated'. However, by technologising the performance beyond this initial process, the approach is taken further in actively involving them in the conceptual, 'dramaturgical' and developmental structure behind our work. This raises various questions in relation to how technologies used in contemporary performance practices shift the role of the audience and redefine the notion of participation. In the piece, they cease to be called merely audience members; they become witnesses, storytellers, experiencers, participants and co-creators of both developing the content and curating it through their interaction.
Love Letters takes this idea of the body and dress as interface further. The rhizomatic manner that occurs through the different modes of interaction with the dress produces various outcomes: computer/controller and software and audience member as creator and performer. Every interaction generates a different outcome, activating a distinctive story from the collection. The productions via these interactions depend on the myriad of possibilities programmed in the software and augmented onto the modular micro-controller. As discussed above, the concept of audience member is speculative. It also raises questions around whom the active observer is if both the technologies and the participant/audience members are performing and curating the content together. The selection process for playing back the material is based on the algorithm coded in the software and influenced by the metadata that occur during the performance because of the different interactions. The recordings were put through a software process that was generative, live and immediate -almost like improvisation -as the playback of the recorded material is unique to each performance due to the interaction with the audience. Therefore, the responsibility of curation is not only taken up by the patch created on the software and the numeric values given by the programmer, but it was also dependent on the audience member's subjective choices of where to pin each letter after reading it aloud. In this way, the process of curating the recordings was democratised and shared rather than having someone solely responsible. Implementing user-curation as the method for display meant that the exhibit was based on participants' subjective arrangements rather than a dogmatic taxonomy. The strategy used here is to homogenise the human actor(s) involved in the decision-making process and allow space for the production of experiential data. As Markopoulos, Moore, and Ruddle suggest, 'when interaction is purely observational, performances tend to involve video displays, computer graphics, audio presentations' and so on. (2004: 8). However, wireless technologies such as those used in Love Letters, are beginning to expand the parameters of observational engagement in performance, 'making the audience an active participant in the making of the piece' (Markopoulos, et al., 2004: 8).
Wearable technologies have mostly been used for utilitarian purposes or in fashionable technology design through smart clothes and performative provocations such as: Kobakant's commissioned Extravagant Electronic funeral gown, also known as The Crying Dress (2012), which was worn by the wife of the deceased commissioner in attendance of his funeral. The dress was made to shed endless tears of mourning. Additionally, (No)Where (Now)Here (2013) by Ying Gao, a series of two dresses created out of photoluminescent thread and embedded eye tracking technology that is activated by a spectator's' gaze, were inspired by Paul Virilio's Esthétique de la disparition [The aesthetic of disappearance] (1989). Preceding this, Gao also produced Walking City Dresses (2011), which were garments that consisted of hidden pneumatic pumps that filled origami-style creases in the fabric used with air. The series of dresses were either activated by proximity and movement sensors, which detected approaching spectators, or reacted to sounds picked-up through a suspended microphone. Another example is the collaborative project Exchange-Dress (2004) by Celine Studder, Sabine Seymour, Marscha Jaggi and Françoise Adler that is inspired by human encounters and fleeting conversations that leave mental marks, traces and impressions. The garment created, uses colour as a metaphor to express that very notion. Triggered by colour-coded bracelets worn by the audience members, and made with proximity sensors, an IR transmitterreceiver and a modular micro-controller, the dress's white luminex fabric changes colour according to the colour of the visitor's bracelet, making each individual encounter between performer and audience visible and unique. These examples of using wearables beyond utilitarian parameters, as with Atsuko Tanaka's Electric Dress given earlier, mediate different ways of perceiving the world around us and have acted as springboards for the remaking of the Love Letters dress through their diverse approaches and contextualisation. However, what makes the garment used in Love Letters different is that firstly it was not created with fashion design/technology intentions but instead with a performance perspective, and secondly it attempts to take the exchange encounter of interaction between dress/costume and audience further by sharing personal stories of previous audiences that are absent at the moment of each performance. This mirrors the notions of presence and absence touched upon by Gao in her piece, as well as the response to fleeting encounters that is colourfully projected through the Exchange-Dress.
As well as inputting the different sound recordings in the software used in Love Letters, the patch created also continuously plays, at a low volume, a soundscape that is made of acousmatic sounds of previous performances of Love Letters put together. The outcome of this was a hubbub of sounds/voices from numerous past audiences in addition to the space's acoustic and location sounds and the resonant frequencies of the different past sites that the piece was performed at. The soundscape was captured using 'two-point stereo recording'. This documenting approach was taken to reflect the notions of presence, absence and in-situ when encountering the love letters heard. Playing this in the background produced a sonic experience for the listener. It created the impression of actually being in a space at the moment of happening. With the soundscape, we attempted to focus on the musical qualities of the sound content rather than using an informative process, shifting the attention from communication to the sonorous tones and textures of the recordings played, as with Alvin Lucier's I am Sitting in a Room (1969). 5 The soundscape in Love Letters played in the background to accompany the stories heard through the dress-interface, offering the audience member/witness an in-situ experience of the content. This transported the experiencers to previous performances, almost providing them with the opportunity to become future ghosts of past performances. LaBelle suggested that it progresses 'into an accentuation of acoustic space whereby the sound source (voice) loses its original shape through the resonance of the spatial situation ' (2006: 126). This is an element that occurs in the soundscape produced for Love Letters, as in each performance the recordings are played and rerecorded along with the acoustic spatial sounds adding another layer to the soundscape. The sound and the voices are disseminated into a much larger interaction, through which the rerecorded, acousmatic voices make the aural soundscape evident through its disembodied reproduction.
As technology becomes an integral part of many modern performance pieces, questions can be raised with regard to how principles of Human-Computer Interaction (HCI) affect the interaction of performer and audience with the interface. This has been addressed by Reeves et al. (2005), who characterise and classify interfaces according to the extent that a performer's manipulation with the interface and its subsequent effects are hidden, obscured or augmented. These can be characterised as 'secretive', when both interface manipulations and resulting effects are hidden; 'suspenseful' when the effects are hidden while manipulations are amplified (for example as in the case of observing someone trying out a Virtual Reality simulator); 'magical' when this relation is reversed (as in the case of a magician performing a magic trick), or finally expressive when both manipulations and effects are amplified (See Figure 5). Viewing the dress in Love Letters as an interface, with which both audience and artist interact (hence blurring the boundaries between a passive observer and an active performer), we can access the performance as being in the 'expressive' spectrum as seen in figure 5. This reveals and perhaps even amplifies the manipulation on the audience's part by their walking up to the performer, reading a letter from the collection and pinning it to the dress. At the same time, amplifying the effects of those actions in the form of the resulting auditory effects through narration of the letter by the dress, as well as alterations to the performance's soundscape, are perceived by all participants present. This is of particular importance as a mechanism for widening audience participation; by keeping to an expressive paradigm not only can the performance attract more spectators while in progress, but it also allows any member of the audience to learn by observing, allowing them to prepare for their own turn of participation in the performance. The format of the dress plays on the concept of ubiquitous technology. Ubiquitous computing includes main elements such as: multimodal interfaces, context-aware or adaptive computing, automated capture, access to live experiences and connecting the physical to virtual worlds -similar to features of performance art. According to Giulio Jacucci, these ubiquitous computing tenets can be related to features found in performance practices, as they share common objectives such as staging and performing embodied experiences (in Ekman, et al., 2016): 352). Other features of ubiquitous computing such as adaptivity and context awareness are essentially reducible to the agency of the system, which need to intervene following certain 'rules' and improvise given certain situations. In this manner, pervasive technology propositions sensing systems that measure and encourage space and sense situations. With the use of such systems in performance, space is configured and performed rather than measured and situations are 'staged' rather than acknowledged by the subjects. As Sheridan et al. state, the aim of these technologies is to aid the performer, who creates the piece in order to tell the story, disclosing a message or engineering an experience for the audience (in Fincher, et al., 2004: 7). Dalsgaard and Hansen (2008) consider interaction as expressive acts of coexperience. They observe how the user is simultaneously operator, performer and spectator, underlining the concept of performing perception. This emphasises how the user/audience is strongly influenced by the awareness that the knowledge of the system engaged with is in itself a performance for others which is similar to the processes that occurs in Love Letters. They maintain that a central component of the aesthetics of interaction is founded in the user's experience of themselves 'performing their perception'. This condition continuously shapes the users' understanding of interaction. Therefore, designing for such interactive experiences necessitates reflecting on theories found in performance studies such as embodiment and social interaction. The decisive contribution of 'multiuser' participation (audience, experiencer) in engagement advocates that a subject's experience and ludic hedonism is ingrained in the embodied, performative interaction with installations and is conveyed with other experiencers in the interactive encounter. This is because the engagement with such systems, as with performance, produces data, which is experiential and accordingly subjective, and for this reason is difficult to capture. Considering this, it can potentially be measured as another layer to what Diana Taylor (2003) calls the repertoire. 6 These modalities are considered non-discursive 'anti-evidence'. In one way or another this is the effect that the interaction with technology causes, as it produces different types of ephemera, which according to Moñuz (1996) do not vanish but are distinctly material. Taking this into account, the use of technology used in our piece may not be directly related to the repertoire but certainly has the ability to produce experiential ephemera; as with the idea of interface, it can be seen as an extension of such embodied practices.

The Dress as Sound Installation
Love Letters places the audience member as the user and experiencer in the position of storyteller and listener, an element that the project uses towards democratising both the communication and presentation of the material. Playing with the conditions of presence and displacement, the user embodies the storyteller by controlling which 'displaced' 'stories will be told. Simultaneously, the user performs the role of the listener by taking in the information played through the garment as interface. The piece intends to put to test the user's interaction with databases of memories and personal testimonies by taking a collection out of its original context. In addition to this, it aimed to develop an approach of mapping digital stories from absent sources into tangible objects, such the costume. The material is combined and a new narrative is generated each time according to the user's choices. In this sense, the documented material collected is re-performed through the user's choice of a subjective narrative. Thus, the dissemination of the material and its curation is up to the user playing with the existing frameworks built into the system.
Working with the medium of sound was selected to reflect the ethos of narrative and orature, in addition to thinking of the voice as sound -considering Aristotle's definition of the voice as sound with meaning (Dolar, 2006: 11, 23). As Linda Sandino propounded, sound art practice offers an effective alliance with practices of embodied cognition, like storytelling, oral history and performance. This is due to the specific arts practices embracing several emotional and theoretical properties that identify with registers found in narrative recordings, such as voice as sound, embodiment, presence and the desire to communicate (2013: 5). Sandino also argues that the process of using recorded testimonies as material for sound artworks reflects several components of Bourriaud's 'relational aesthetic' (2013: 5). This mode is characterised by a collection of artistic practices that theoretically and practically draw on human relations and their social context, instead of concentrating on an independent and individual space (Bourriaud, 2002: 113). This is a distinctive context that practices of the repertoire encompass, using narration as a technique to relate and communicate, and to further create a collective remembrance of the event that is taking place. The personal individual recollections found in the recordings often enclose evidence about how things felt to individuals, and as discussed earlier in this paper, they hold information about the narrator, due to the accents used, the turns of expression and the para-linguistic exclamations. These components are as enlightening as the stories themselves and reveal the time and place of narration, performance and recording. LaBelle suggests that sound art pieces provide audiences with an auditory experience that 'situates the listener within an intensification of immediate experience ' (2006: 197). This appears to underline components of interactive art, which create a sense of existence through engagement and an exchange demonstrated through the work contextualised in this article.

Conclusion
The artistic work discussed in this article attempted to foster a cross-fertilisation between arts, humanities and sciences and to accumulate writing around performance theory, sound and computer science. The technology used in the performance was not only a tool to enhance the component of audience engagement, but instead it also used the medium of performance as a platform for wider technological experimentation. By reworking the piece through augmenting the dress or costume with technology, we aimed to explore how pervasive technology can support reminiscing and facilitate storytelling. As explained we are 'storied' beings; our identities are built with social and individual stories; we interact through sharing stories and we learn through stories.
Thus, Love Letters opened up avenues for thinking about different modalities of text/narrative delivery. This is manifested through thinking about the body and its flesh as an interface of communication and a mode of capturing text. Additionally, it is also considers the dress as a type of technology and interface. This is not least because of its linguistic and performative properties in the material and cultural sense, but also because of how it is utilised within each performance, whereby it becomes physically and conceptually attached to the audiences' reminiscences.
The augmentation of technology onto the dress shifted the roles of performer and audience as they become active participants and co-creators of the piece, which through each and every interaction with the garment they receive a different experience. It is important that in the model of representation used in Love Letters, and especially for exhibiting oral history or personal narrative, a collective creation of narrative and interpretation should be allowed, as this would potentially acknowledge a past co-creation of a series of performative or communicative acts. In this context, visitors to the exhibition or the audience to the performance become enfranchised through different strands of participation and co-create a further narrative, adding more layers of interpretation to the materials (letters) exhibited, and the stories (sound) embedded on the dress. When contextualising the shift of roles and exchange between audience and performer that occur through such modes of participation it is useful to look at Bourriaud's relational aesthetics: '[t] he status of the viewer alternates between that of a passive consumer, and that of a witness, an associate, a client, a guest, a co-producer and a protagonist' (Bourriaud, 2006:. 168). Bourriaud also points explicitly to the duty of the artist, because of the 'symbolic representations' exhibited, that facilitate the notions of interaction and communication rather than 'bare' participation. He maintains: Their works bring into play modes of social exchange, interaction with the viewer inside the aesthetic experience he or she is offered, and processes of communication in their concrete dimensions as tools that can to be used to bring together individuals and human groups (2006: 165).
With the re-making of Love Letters we intended to create a performance framework that can be used for the curation and dissemination of oral and written memories. In a performance setting, the 'gedankenexperiment' served to develop a model that could be transferred for exhibiting costume histories in culture heritage environments. This presents the potential for encapsulating the audience/experiencers/interactors in the story, which are present in the reminiscences of the specific garment used. In this way, the garment speaks its history and its memories are triggered by its audience. Through using performance to engage with technology in Love Letters (vice versa), and thus developing a system whereby the audience member becomes experiencer through learning via process within the use of creative technologies, the performance's interactive properties are not being isolated and substituted by the technological apparatus. Love Letters is a provocation rather than something fixed and complete. It is an ongoing attempt towards devising interactive approaches for the purposes of engaging with different oral histories and personal recollections -as well as written narratives -with a transferability to other contexts of learning about history and learning through process and interaction. This is achieved by using performance as a tool to showcase such tools. In this manner, it can be suggested that the format we propose of using technology in performance or performance in technology can provide a common 'algorithm' or language for the discussion of technology-based performance, which supports discourse between performers, curators, technologists, and researchers/theorists from different fields.
2 The work was initially performed at the Performance and Live Art Platform (2012) in Cyprus as a performance happening. Since then, it has taken the shape of a performance lecture, a sound installation and a durational, processed-based performance installation. The performance's shape may have shifted several times, however the work's main content -which through every performance emerges from the very act of participation, engagement and interaction of the audience -remains unchanged. This on-going piece has been performed more than five times in different countries across the EU and at renowned performance festivals and conferences such as: Performing Documents (2012), Performance and Live Art Platform (2012, 2014), Tempting Failure (2013, 2014, Latitude (2015), and iDocs (2016). 3 The article has been written by the three individuals from different fields (Performance, Music, Computer Science) with the attempt to merge their ideas on the relationship between technology, performance and audience, towards finding crossovers between their work. In this paper, we use our interdisciplinary and ongoing performance project as the primary case study to experiment, to invoke further interdisciplinary dialogues between artists, researchers and technologists. The structure does not comprise of three individual sections reflecting each person's perspective, but rather echoes our shared desire and attempt to fuse these 'categories' and each person's' ideas into one. 4 Flusser realises the human body to be composed of both genetic and cultural memory (in Ascott, 1999: 86). 5 Lucier recorded his voice, played it back into a space and repeated this process of playing back and recording several times, until his words were no longer discernible and became sound. 6 Within Taylor's thinking, the repertoire/embodied cognition produces a type of historical knowledge that is rejected from orthodox or dogmatic archival practices, as it denotes the domain of corporal gestures and speech: 'alternate modes of textuality and narrative like memory and performance' (Muñoz, 1996: 10). As Muñoz states they 'reformulate and expand our understandings of materiality ' (1996: 10).