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SCIENTIFIC AMERICAN SUPPLEMENT NO. 401




NEW YORK, SEPTEMBER 8, 1883

Scientific American Supplement. Vol. XVI, No. 401.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.


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TABLE OF CONTENTS.

I.    CHEMISTRY.--On the Different Modifications of Silver Bromide
      and Silver Chloride.

      Analysis of New Zealand Coal.

      On the Determination of Manganese in Steel, Cast Iron,
      Ferro-manganese, etc.

      Manganese and its Uses.

      Ozokerite or Earth-wax. By WILLIAM L. LAY. A valuable
      and instructive paper read before the New York Academy of
      Sciences.--Showing the nature, sources, and applications of this
      remarkable product.

      On the Constitution of the Natural Fats.

II.   ENGINEERING AND MECHANICS.--Improved Spring wheel
      Traction Engine.--With two engravings.

      An Improved Iron Frame Gang Saw Mill.--With one large
      engraving.

      The Heat Regenerative System of Firing Gas Retorts.--Siemens'
      principle.--As operated at the Glasgow Corporation Works.--With
      two engravings.

      A New Gas Heated Baker's Oven.

III.  TECHNOLOGY.--How to Produce Permanent Photographic Pictures
      on Terra Cotta, Glass, etc.--With recipes and full directions.

      How to Make Paper Photo Negatives.--Full directions.

      Some of the Uses of Common Alum.

      An Improved Cloth Stretching Machine.--With an engraving.

      Purification of Woolen Fabrics by Hydrochloric Acid Gas.

      Apparatus for Preventing the Loss of Carbonic Acid in Racking
      Beer.--With an engraving.

IV.   ELECTRICITY.--Application of Electricity to the Bleaching of
      Vetable Textile Materials.--With figure of apparatus.

      Table Showing the Relative Dimensions, Lengths, Electrical
      Resistances, and Weights of Pure Copper Wires.

V.    ASTRONOMY.--The Solar Eclipse of 1883.--An interesting abstract
      from a report of C. S. HASTINGS (Johns Hopkins University), of
      the American Astronomical Exhibition to the Caroline Islands.

VI.   NATURAL PHILOSOPHY.--Recent Experiments Affecting the
      Received Theory of Music.--An interesting paper descriptive of
      certain experiments by President Morton, of Stevens Institute.

      The Motions of Camphor upon Water.--With an engraving.

VII.  ARCHITECTURE.--Suggestions in Village Architecture.--
      Semidetached villas.--Bloomfield crescent.--With an engraving.

      Specimens of Old Knocking Devices for Doors.--Several figures.

VIII. ARCHAEOLOGY.--A Buried City of the Exodus.--Being an account
      of the recent excavations and discoveries of Pithom
      Succoth, in Egypt.--With an engraving.

      The Moabite Manuscripts.

IX.   AGRICULTURE. HORTICULTURE, ETC.--The Queen Victoria
      Century Plant.--With an engraving.

      Charred Clover.

      A New Weathercock.--With one figure.

X.    MISCELLANEOUS.--New Monumental Statue and Landing Place
      in Honor of Christopher Columbus at Barcelona, Spain.--With an
      engraving.

      Scenery on the Utah Line of the Denver and Rio Grande Railway.

      Captain Matthew Webb.--Biographical sketch.--With portrait.

      The Dwellings of the Poor In Paris.

      Shipment of Ostriches from Cape Town, South Africa.--With one
      page of engravings.

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MONUMENT TO CHRISTOPHER COLUMBUS, AT BARCELONA, SPAIN.


The cultivated and patriotic city of Barcelona is about to erect
a magnificent monument in honor of Columbus, the personage most
distinguished in the historic annals of all nations and all epochs.
The City of Earls does not forget that here the discoverer of America
disembarked on the 3d of April, 1493, to present to the Catholic
monarchs the evidences of the happy termination of his enterprise. In
honoring Columbus they honor and exalt the sons of Catalonia, who also
took part in the discovery and civilization of the New World, among whom
may be named the Treasurer Santangel, Captain Margarit, Friar Benardo
Boyl, first patriarch of the Indies, and the twelve missionaries of
Monserrat, who accompanied the illustrious admiral on his second voyage.

In September, 1881, a national competition was opened by the central
executive committee for the monument, and by the unanimous voice of
the committee the premium plans of the architect, Don Cayetano
Buigas Monraba, were adopted. From these plans, which we find in _La
Ilustracion Espanola_, we give an engraving. Richness, grandeur, and
expression, worthily combined, are the characteristics of these plans.
The landing structure is divided into three parts, a central and two
laterals, each of which extends forward, after the manner of a cutwater,
in the form of the bow of a vessel of the fifteenth century, bringing to
mind the two caravels, the Pinta and Nina; two great lights occupy the
advance points on each side; a rich balustrade and four statues of
celebrated persons complete the magnificent frontage. A noble monument,
surmounted by a statue of the discoverer, is seen on the esplanade.

[Illustration: MONUMENTAL LANDING AND STATUE TO COLUMBUS, AT BARCELONA,
SPAIN.]

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The commission appointed in France to consider the phylloxera has not
awarded to anybody the prize of three hundred thousand francs that was
offered to the discoverer of a trustworthy remedy or preventive for the
fatal grape disease. There were not less than 182 competitors for the
prize; but none had made a discovery that filled the bill. It is said,
however, that a Strasbourg physician has found in naphthaline an
absolutely trustworthy remedy. This liquid is poured upon the ground
about the root of the vine, and it is said that it kills the parasites
without hurting the grape.

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SCENERY ON THE UTAH LINE OF THE DENVER AND RIO GRANDE.


Mr. R.W. Raymond gives the following interesting account of the
remarkable scenery on this recently opened route from Denver to Salt
Lake:

Having just made the trip from Salt Lake City to this place on the
Denver & Rio Grande line, I cannot write you on any other subject at
present. There is not in the world a railroad journey of thirty hours
so filled with grand and beautiful views. I should perhaps qualify this
statement by deducting the hours of darkness; yet this is really a
fortunate enhancement of the traveler's enjoyment; it seems providential
that there is one part of the way just long enough and uninteresting
enough to permit one to go to sleep without the fear of missing anything
sublime. Leaving Salt Lake City at noon, we sped through the fertile and
populous Jordan Valley, past the fresh and lovely Utah Lake, and up the
Valley of Spanish Fork. All the way the superb granite walls and summits
of the Wahsatch accompanied us on the east, while westward, across the
wide valley, were the blue outlines of the Oquirrh range. One after
another of the magnificent canyons of the Wahsatch we passed, their
mouths seeming mere gashes in the massive rock, but promising wild and
rugged variety to him who enters--a promise which I have abundantly
tested in other days. Parley's Canyon, the Big and Little Cottonwood, and
most wonderful of all, the canyon of the American Fork, form a series not
inferior to those of Boulder, Clear Creek, the Platte, and the Arkansas,
in the front range of the Rockies.

Following Spanish Fork eastward so far as it served our purpose, we
crossed the divide to the head waters of the South Fork of Price River,
a tributary of Green River. It was a regret to me, in choosing this
route, that I should miss the familiar and beloved scenery of Weber and
Echo canyons--the only part of the Union Pacific road which tempts one
to look out of a car window, unless one may be tempted by the boundless
monotony of the plains or the chance of a prairie dog. Great was my
satisfaction, therefore, to find that this part of the new road,
parallel with the Union Pacific, but a hundred miles farther south,
traverses the same belt of rocks, and exhibits them in forms not less
picturesque. Castle Canyon, on the South Fork of the Price, is the
equivalent of Echo Canyon, and is equal or superior in everything except
color. The brilliant red of the Echo cliffs is wanting. The towers
and walls of Castle Canyon are yellowish-gray. But their forms are
incomparably various and grotesque--in some instances sublime. The
valley of Green River at this point is a cheerless sage-brush desert,
as it is further north. To be sure, this uninviting stream, a couple of
hundred miles further south, having united with the Grande, and formed
the Rio Colorado, does indeed, by dint of burrowing deeper and deeper
into the sunless chasms, become at last sublime. But here it gives no
hint of its future somber glory. I remained awake till we had crossed
Green River, to make sure that no striking scenery should be missed by
sleep. But I got nothing for my pains except the moonlight on the muddy
water; and next time I shall go to bed comfortably, proving to the
conductor that I am a veteran and not a tender-foot.

In the morning, we breakfasted at Cimarron, having in the interval
passed the foot-hills of the Roan Mountains, crossed the Grande, and
ascended for some distance the Gunnison, a tributary of the Grande, the
Uncompahgre, a tributary of the Gunnison, and finally a branch, flowing
westward, of the Uncompahgre. A high divide at the head of the latter
was laboriously surmounted; and then, one of our two engines shooting
ahead and piloting us, we slid speedily down to Cimarron. It is in such
descents that the unaccustomed traveler usually feels alarmed. But the
experience of the Rio Grande Railroad people is, that derailment is
likely to occur on up-grades, and almost never in going down.

From this point, comparison with the Union Pacific line in the matter
of scenery ceases. As everybody knows, that road crosses the Rocky
Mountains proper in a pass so wide and of such gradual ascent that the
high summits are quite out of sight. If it were not for the monument to
the Ameses, there would be nothing to mark the highest point. For all
the wonderful scenery on the Rio Grande road, between Cimarron and
Pueblo, the Union Pacific in the same longitudes has nothing to show.
From an artistic stand-point, one road has crossed the ranges at the
most tame and uninteresting point that could be found, and the other at
the most picturesque.

At Cimarron, the road again strikes the Gunnison, and plunges into the
famous Black Canyon. In length, variety, and certain elements of beauty,
such as forest-ravines and waterfalls, this canyon surpasses the Royal
Gorge of the Arkansas. There is, however, one spot in the latter (I
mean, of course, the point where the turbulent river fills the whole
space between walls 2,800 ft. high, and the railroad is hung over it)
which is superior in desolate, overwhelming grandeur to anything on the
Gunnison. Take them all in all, it is difficult to say which is the
finer. I have usually found the opinion of travelers to favor the
Gunnison Canyon. But why need the question be solved at all? This one
matchless journey comprises them both; and he who was overwhelmed in the
morning by the one, holds his breath in the afternoon before the mighty
precipices of the other. To excuse myself from even hinting such folly
as a comparison of scenery, I will merely remark that these two canyons
are more capable of a comparison than different scenes usually are; for
they belong to the same type--deep cuts in crystalline rocks.

Between them come the Marshall Pass (nearly 11,000 ft. above sea-level),
over the continental divide, and the Poncha Pass, over the Sangre di
Cristo range. This range contains Harvard, Yale, Princeton, Elbert,
Massive (the peak opposite Leadville), and other summits exceeding the
altitude of 14,000 ft. To the east of it is the valley of the Arkansas,
into which and down which we pass, and so through the Royal Gorge to
Canyon City and Pueblo, where we arrived before dark on the day after
leaving Salt Lake.

Salt Lake, the Jordan Valley, Utah Lake, the Wahsatch, Castle Canyon, the
Black Canyon of the Gunnison, Marshall Pass, Poncha Pass, the Arkansas
Valley, the Royal Gorge--what a catalogue for so brief a journey! No
wonder everybody who has made it is "wild about it!" If enthusiastic
urgency of recommendation from every passenger has any influence (and I
know it has a great deal), this road will continue to be, as it is at
present, crowded with tourists. It furnishes a delightful route for
those who wish on the overland journey to see Denver (as who does not?)
and to visit Colorado Springs and Manitou. All this can be done _en
route_, without retracing the steps.

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PHOTOGRAPHY APPLIED TO TERRA-COTTA AND OPAL GLASS.


In the natural course of things it must necessarily have occurred to
practical men to utilize photography in the case of terra-cotta, as it
has already been employed in connection with so many other wares; but I
have not to this day known of its successful application to terra-cotta.
Now this is strange, if one considers how fashionable _plaque_ and plate
painting have become of late, and the good photographic results that
are easily obtained on these as on sundry articles of this same "burnt
earth." Portraits, animals, landscapes, seascapes, and reproductions are
one and all easily transferred, whether for painting upon or to be left
purely photographic. As a matter of business, too, one fails to see
that it would not be remunerative, but rather the contrary. It was with
something of this feeling that I was led to try and see what could be
done to attain the end in view, and as I knew of no data to go by, I had
to use my own experience, or rather experiment on my own account.

Since emulsion was constantly at hand in my establishment, in the
commercial production of my gelatine dry plates, it was but natural I
should first have turned to this as a mode of obtaining the desired
results; but, alas! all attempts in that direction signally failed--the
ware most persistently refused to have anything to do with emulsion. The
bugbear was the fixing agent or hypo., which not only left indelible
marks, but, despite any amount of washing, the image on a finished plate
vanished to nothing at the end of an hour's exposure in the show window.
There was nothing left but to seek other means for the attainment of my
object. I would not have troubled the reader as to this unsuccessful
line of experiment but that I wished to put him on his guard and save
him useless researches in the same direction. To cut matters short, the
method I found best and most direct was the now old but still excellent
wet collodion transfer. I will now proceed to detail my system of
working to facilitate the matter to the inexperienced in collodion
transfer.


TERRA-COTTA PHOTOGRAPHY IN PRACTICE.

The first and indispensable operation, in the preparation of the surface
to receive the transfer, is the "sizing of the surface." It simply
consists of a solution of gelatine chrome-alumed, as follows:

  Gelatine.                           10 grains.
  Water.                               1 ounce.
  A trace of chrome alum.

Coat with a soft camel's hair brush and let dry. It is needless to say
that numbers of _plaques_, plates, vases, etc., may be coated right off,
and will then be ready for use at any time.

Having settled on the subject and carefully dusted the negative, as well
as placed it _in situ_ for reproduction, the next thing required is a
suitable collodion, and the following will be found all that can be
desired:

  TRANSFER COLLODION.

  Cotton.                      3 drachms.
  Iodide of cadmium.          65 grains.
  Ammonium iodide.            25   "
  Bromide of cadmium.         19   "
  Ammonium bromide.           11   "
  Alcohol.                    15 ounces.
  Ether.                      15   "

The plate thoroughly cleaned and coated with the collodion is now
transferred to a bath, as follows:

Nitrate of silver (common) 25 grains to the ounce.

Made slightly acid with nitric acid.

After sensitizing, the plate is exposed in the usual way and taken to
the room where pictures are ordinarily developed, and _quantum suff_. of
the following poured into the developing cup to bring out the image:

  DEVELOPING SOLUTION.

  A Winchester of water, i.e.  80 ounces.
  Protosulphate of iron.      240 grains.
  Citric acid.                240   "

Or the following may be used:

  Pyro                          3 grains\
  Citric acid                   2   "    } per ounce of water.
  Glacial acetic acid          30 drops /

After perfect development the picture is well washed and then fixed in a
saturated solution of hypo.; after which it is thoroughly washed.

It will now be found that the picture is not altogether satisfactory; it
lacks both vigor and color. To improve matters recourse is now had to


TONING.

  Gold.    1 grain.
  Water.   5 ounces.

With this a very fine depth is soon attained, and a nice picture the
result. Leave out the toning, and only a poor, sunken-looking picture
will be the outcome; but directly the toning bath is employed richness
at once comes to the fore. I have, however, known of instances where the
picture needed no toning.


OPAL PRODUCTION IN PRACTICE.

This is still a secret with some in the profession. A limited number
of workers have succeeded in bringing out good opals, and their _modus
operandi_ is kept from the many. Now this is a pity, when one considers
the great charm attached to a good picture on opal, with pure whites and
rich blacks, and in many localities the demand that might be created for
them. Apart from their beauty, another charm attaches to opals--their
absolute permanence; and this, it must be allowed, is no trifle. What,
in fact, can be more painful to the worker who values his work, and sets
store by it, than to feel it must ere long fade and pass into oblivion!
A properly executed opal will no more fade than the glass pictures so
common at one time, and which, wherever taken care of, are as perfect
now as they were when first taken.

Now, excellent pictures are to be made on opals by means of emulsion;
but I propose first taking the transfer method (mainly applicable to
ground opal and canvas) as given above for pottery, since in practice
it is found very ready, easy of manipulation, and safe. The details are
much