-

-. . _-._ --__-" Sinnll bituminous conls, othcrwisc coking conle. 
. . . ThcHe conls will hnrc to lw? suitnbls for loconioti~-c gmtcs, mixcd in n certain proportion with less bituminous conls. 
"They nrust bc srich RB to give nn ngglutinntcd C O ~C when mixcd with nn incrt mntcrinl (qunr!z) in thc pro-' poGion of 70 per cent. qunrtz n n d 30 per cent. conl. 
A close inistiire nindc up in the nborc proportions, finely ground, hrntcd bright red, until coniplctc disnpjmrnncc of volntilc ninttcrs in n ])orcclniii cruciblc nntl in n reducing ntinosphcre, will hnvc t o ng%lutinntc in n mnss which ninst tm firm or n t lenst must not fnll into cinst iinclrr thc prcssurc of tlic fingers. 
" I'rcvious t o the plncing of the niirture into tlic mufXc thc lntter will hnvc bccn brought to tlic clesirccl tcinlwr. 

at we."

This mctliod diffwccl from Cnmprcdon's : (1) in thc finrness Of the qunrtz nntl snnd, both k i n g ncnrly ns fine ns flour--unless sonic dcfinitc size wcre given this might ensily cnnsc nnnlysts in different, plnccs to find tliffcynt rraults. 
( 2 ) The coking in n rcclucinr: ntiuosphcre. I'liia wns n dcciclcd stc in thc right direction and conltl cnsily tnnnngcci ~i y pyncing tlic snlnll crucible contninirig t ~i r inisture to be cokccl in n lnrgcr crucilib nnd ~iiicking all round with sinnll frngmcnts of chnrconl. This did nwuy with nny ritintion of the results bj' removing the opportunity of osidetion of thc thin film of ngglutinniit. He wonld likc to sec n titnnclnrd rncthocl adopted cmlmdying tho best fcntures of the nbovc nncl would suggcst tirot I)r. h n n might done, or in conjunction with n smnll committee of the &wtion, foriiiiilntc n method. It is illuatruted in Fig. 1. 
111 tho prosent pnpcr wu giro tioniu of tlio rcsiilts obtiiinud by nieiins of tliu iilipnr'nt~s rind ulso somo consitlorntions of tho best wny of usprowing theso results. 
In wirryiug out thu tcstr, it wns found dcsirublo to exnniino first of rill tliu conclitiori of the skin bcforo onturing tliu jiucr liquor, iind in this m y tliu iilipnrntus proved of grcrit iiso in showing tho dcgrcu uf ~i ~u ~n p i n g tho skins liud received during t hu liming or prcpnriilory proeusws. nntl of equiil nso for this piirposu 11s for the origin111 pir1iose for which it w i s cle~igned. Wl~on n skin is snbjcctccl to siicccwivo incrcnxing lontlg, and tlio load roniovctl cncli tinic, it is foiincl thut oven unclcr n very ninnI1 lontl it cloos not ns n rulo entirely rocover its orisinnl tltickncss. Iwt tlint n ccrtnin nnionnt of iict or purinnncnt coniprcssion t n k w plnco. Tho difforuncc Iiut\\ con tho totnl untl tlic 1)crninncnt coniprossion is tho clnstic coniprcanion, nntl wo proposc to rncminru tho resilience of the skin by tho ~icrccntogc rntio of tho clnstic to tliu totnl coniprcsvion. 
To nntlcratitnrl wlint tnkcs plncc rliiring tlic coniprcssion of wet skin in our nppnrntiis tvo rnny consider tliu rkin to bo of tho nntiirc of n sponcc, tho w:rlls nf ~vliicli Iiaro mrying clcgrccs of firninuss, clnsticity, iind tliickncss uccordins ns tho skin is in tho litnetl, the d~~lintcd, or tho p o r e d condition. Tlio voliirno coniprc.ssibility is prohuldy nogligililo in nll cntiw, but n certnin portion of tlic nkin substenco nlwuys flows iintler prcssiiro Iicyontl tlio jnws of tliu nincliinc. Tho principsl cffcct of putting prcssuro on tliu skin ia to climinhli tlic sizo of tliu intorsticcs or cnvitics in it with conconiitnnt osjiiilsion of writor. l'lic rdlc plnyctl I J ~ tho w t c r BY B I I L ' ~ is only to 4ow clown tlic proccns of coinprcs4on: it slioiild not nflect tlic finel u q ~~i l i l ~r i ~~n ~. 
As t,lio nkin is pcrfuctly sut, nntl, wlict licr oxirniinctl under wutcr or not, niiist IJC consitlcrctl coinplot.cly nnrronntlorl 1~y wntcr, tlic siirfuws i i f contiict 1)ctwccii wuter and skin-fibro nro not nacctcd to nny a qirucinblu ustcnt by tliu us icrinionts. nnrl so cnpillnrity Jays prncticnlly no pnrt in tlicni. It in olivious tlint tliu sizo of t.110 jnws will bo of tlic vcrr gruntcst iniliortnnco in dctcrniining tho tinio tnkcn to dttiiin cqiii~i~~rinni, since with lnrgu jnws tlioro is littlo opportunity for tliu wntor to uucnpo nlong tho ctlgcs. Ibsitlos, tho flowing of tlio skin ns such will yrobnldy Lo hinifercti t o so gi-cnt an oxtunt by ltrrgn jnws tlitit it i rc cloul~tful dictliur, oven with tho ~irol~ortionntuly Iiunvior loritl~ requirctl to Iwoduco tho nnniu ntrcswq. ns grcut coniprcssion nil1 I)o obt.ninctl with large us with ~n i o l l jnwn. 'I'liu nizu of tlio j u s s slioiilcl tlioruforu bc npocific:illy stutod in osporinicnts on tho coin )roscjion of skin. Professor Proctttr 1111s. x i i q p t e d to 11s tfiirt thu flow of wntor froni tho skin inirlit I)u rcry g+ly facilitntotl by plucing n circulnr Jisc of it between ~i ~u c u s of p r o u s ti10 in n tub0 undcr water, nntl tlint tlie flow of nkin substunco might ill this wiry bo iiiliibitcd. \Yo pro~msc to ruvurt to this sugycstioii in our futuru ox pcri niants. 
111 tho oxlarimoiits wo Iiavo cnrriud out with tliu skin in nir, wc liavn usunlly nllowud tlireo niinutcs for oncli rending. opportunity of oxprcs&ig oiir qrcot indobtodnw to Professor Proctcr, nt whoso suggestion we fiwt carried out crporinicnts undcr wntcr. 
Fm. ! ! . 

TIIIIc ill nlinlltc.~.

\\'u Iinre nlso enrrid out cspcrinicnts ~i t l i 20 per ccrlt. qclatin. Huru tlicro is no oslircsnion of wntcr, nncl nj'thc volunio t!oniprcssildity of gihtin is cluitc riu~lieiblo tlic ~Iinriniitioii of thickness in conipIut~Iy coinliunihtcti ~) y I~iilgin out nt tlm pidcs. Owing to tlio nbsonco of 1wrl.s. tlic gckrtiii. ns wits to bo ospoctctl, is w r y consitlcrobly firniur thnii nny of our skins iintlcr tho prcssiircs wu linvu on~ployctl. It is Rho nIninst coinplctelg rcsilicnt,, nnd tlin virliio of E rtppronclicn constitiicy ns wit11 a pcrf~wtly nln+tic body. A s in riinilnr usporinionts oii tlie clnsticity of titliur siibstirnccs, it i:r not to bo ospcctotl tllet tlio sizu of the jntvs will vury uprirccinl~l~ nffcct tlio rolnt,ion htwccn coni )ru4on nncl npucific lond. \ \ ' u Il:rvo fourid tlint the rswlts nro very qrc:ctly iniprovtd IJ trllowing tho gclntin to stit botwecn t ~i c jaws of tiiu ninc%iiic : ~I I orrors diiu to unuvun contnct of tlie j l r w wlticli uru vory noticcnblu rindur sniull conil)rcssion t h i s dirnppunr. \Yo Iinvu nlso fountl thnt tlio firrnncss of tho qolirtin vory upprecinbly incrcnscs for poinu tiinc nftcr sutting. Thus n 20 par cent. fit-lrrtin jclly gnrr II vuliic of I070 graniu pcr sq. cni. for 15 ii~inictlktt~Iy nftcr sutting. but 18 lioiirs nftcr sctting n vnliio of 1700 wild obtnined iintlcr niniilnr con11i~ion.q. Tnlh 1 nliows tho hliavioiir of two tliflcrunt jullios set butrvoen tfiu dies of our ninehinu. After cinch coinprc?uzi~n, tho loiitl $us ruletisatl untl tho result.ing thick~ioss 1, nionsiirud. 
'l'lie uspurinients 011 qoliitin are inturcst.iny, 11s nffortling UII intlicntion of tho probriblu 1)ulinviocir of tho ' I jelly wutcr " in u &in to wliicli itn olirnticity is probnbly niniiilv IIW. .is is known, tliu uxporiniuiits of Hardy, ~i i t s c ~~~i , nntl otliurn linvu rcliowii tlint n golntin jelly coneiats of t,wo d i 4 n c t ~iliant!s. tho onu ricliur, tho otlicr poorur in gelntiii. According to tliu " uniulaoitl " tlicor oncli of tlicsc ptiosrs iii its turn is i t vury Iinu cniulaion n t t w o tlistiiict liquids ; chistic tlufornintion woiiltl tliiin bo cqnivnlcnt to t l ~c dufornirrtioii of tlie splioricnl tlrolis of tho ~I I I I I ~S ~O ~. 
T l ~c ~c woulcl rucovur their *tinpu rrftcr rernovtii of the ntrcas owingr to tliu forcw of rnpillnrity. A niniilnr usplsnrtion woi~lcl lioltl for tliu I~ulitrvioiir of tho jelly-wtrtcr in n skin. 
Chr csporiinunt,s on tho coniprcssioii of sliins liirvo yioldcd tho inturesting rewlt tlitrt nl)oru loath of n1)oirt 100 p i n s pur sq. [April 30,1019. 

impcrfcct contnct of thc ]R\VS-JI

view wliicli tlcrivcs somc support from thc csperii cnts on golntin dcscribctl nborc, nntl also from tho fnct tint ~csults morc ncnrly npproxirnntin to the lincnr rolntion arc obtnincd in ox erinicnts cnrrici out nnrlor wntcr-wc inny then by n simpFc iroccss of cstrnpolntion cnlcirlntc vnlucs of E .corresponding to very snitill loncla. Thus tho constnnt b, whicli is thc vnliro of E corrcsponcling to n zero lond, niny bc cnsily foirncl from our cspcrinicnts, c.g., by siibtrncting tho diffcrcncc bctaccn tlic vnluca of 15 n t 200 nnd 100 grme. pcr sq. cm. lontl from tho mluc of E n t 100 grins. pcr sq. CIII. Wc niny on11 tho rnlric so found thc firinncss of tlic skin iinrlcr zero lond, or pcrlinps-if wc nilopt tho ricw thnt tho skin nppronches n stntc of truo clnsticity nt w r y sinnll londs-tho motluhis of clnsticity of tho skin. Tho othcr constnnt, n, clinrnctcrising tlic bclinvioiir of tho ekin, rnny bc rcn~lily found from our cspcrimcnte, cg.. of water. n ndhtion to tliis, tlicrc will bc n cortnin nincui~t of comprcnsion duo to thc tluformntion of tho skin RIllJcitflnC(l nnd (lcpcnding on tho jclly xntcr, nnd this comprunsioii will probably bu simply j)ropurtiann~ to tho lond. Tlicsu nssumptions lend to tho cquntion 1 = f +nc+@-'-C!,p in which 1 is tho thioknosfi of tho skin iinclcr tho prc~suro p, f i R tho volume of fibre siibstnncc plus jolly-wator For tinit Rurfncc of Akin unrlar zoro lo~icl. n tho voliinic of tllc iiitur[ibrillnry wntur untlur the sonic conditior~r, n + f tt1118 tho thicknws of tho skin undcr zero lond, c=2*518 tho bnzc of tlic nnturnl lopwithins, nntl Cl nnd Ct constlints govcrnin rcspoctivcly tlic coniprcsFion tliic to tho cxpiilsion of intcrfifrillnry wntcr nnd to tho dcformrltion of tlic Rkin siibstnncc. It is wry clonbtful, hotvcrcr, whcther nn cqiintion of thc nbovc form will oxprcrs tho rcsiilts obtninccl b us so fnr, ns wcll ns tho cmpiricnl rclntion cnuncintcd Tho rcsilioncy of tho skin wns dwnys dctcrlnined undcr wntw ns exp~iiinct~ nliovc. For tliis purposo n sinnll hrnss cnpsiilc wns prcpnrctl \vliicli could 110 nioiintcd on tho lower jnw of our mncliino nncl into which nn niixilinry jtrw of 1 sq. cni. siirfiicc ~irotriiclctl. I'nblc 12 cxprcsscs thc rcwlta obtnincd. It will bc seen thnt, n~ensiircrl nndor thcro conditione. tho rcsilicncy of ptierecl ronn is nbout 20 por ccnt., thnt of n linictl elicep-skin botwecn 50 nntl 80 pcr cent., anti tlint of n dclinicd shecpskin nlso nbout 20 pcr ccnt.. Tho bchnvioer of cfalirncrl skins, xhich, ns cqilnincd above, nrc slightly lass firm tlinn pi~crccl, rinclcr it prcssuro of 100 grim. per sq. cm. cnusctl us sotno surpriec. 'Yo furtlicr eliicidntc this inrittcr wc hitvc cnrricd out. tho followin:: cspcrinicnts. By t.lm crnrninntion of cight tlificrcnt sltins first in tho clolimed nntl then in tho pucrcd condition we hnrc fount1 thnt tliu witcr-content in both stngcs of ini~nnfnot~~rc is prncticnlly itlcnticiil : tlius in o m coso x o obtnincd for delimcrl skin 83.9 por cent., for puorcd skin 84.2 per cunt. wntcr. 'J'hut tho nsh-content of 11 skin incrcnscs chiring pucrinq nntl ifi grentor tlinn thnt of n ~voll-clclimccl skin hns nlrcaclv been stntccl in Wood: Thc Pucring, B~rting, otc., of $kine, p. 38. 
On sonkirig tho tlcliined nntl puerctl skins in 00 per cent. nIcoh01 for 2 ilnys nncl ngnin tnnking n test tlic vnlues 
d o v c .
Dclimed skin E=JBO I'ncrccl skin 1 L 2 6 1 nliicli is tho proportionntc tliffcrcncc we cxpcctcd bctwcon tho two skins. 
\Vith rttprd to tho clifloronres in tho rcsults obtninod for diffcrcnt pnrts of the Rnnic skin, wc find tlint. tho rnrintionn nrs vcrv much of the snmc orclcr ns tliobc found for tho brcnkirig strnin of lciitlicr by Professor Pncsslor,* nntl this fnct niirEt bo borne in niind in using tho ~iictliotl. 
Tho fiimplcst wny is to tiikc snniplc~ from the neck nnd butt of tho skin. 'L'lic thickncss found will ciinblo cino t o jirdpo if tho picco tnken is nbout the nvcrnpo. l'iecoa too thick or too thin should t c rcjoctotl. I n prnctirc it is wcII-nigh impossiblo to give nttantion to cucli indivitlunl skin. If thorcforc two ~ikins nrc tnkon, one rcprcwnting tho firmest nntl t,Iic othcr the softofit, tho con~pnrison of the figures olitiiinetl ia wry oftun of grcnt use. 
I n conclu~ion wc wish to clrnw nttcntion oncc inore to tho nriyinnl objcct of tlio rcsciircli, wliicli wnfi t o dovific n ~netliocl for esprcs~inji ~iittiicricd/y tlic nniount of rlcplotion r~ndcrgono by skin8 in thc pucwing proccss, so ns to mnkc rccords for futuro rcfcrencc and compnri~on. 

TADLE I.


00.8

Theso clntn pivc riac to srrornl interesting considerntioris : [ 1) 3) C.C. of urine i n 100 prnis. of flock wnulil furnish tho nmxinriini ninount of solulle chlorides pcriiiittcel by t lie llng Flock Act. 'l'his scciiis n lnrgo pro]iortioii of iliipurity : Imt tlio Act Imlinbly nlloas for t i n ninount of cliloriiic tluc t o othcr sources. 
(2) One p r t of diloriiio in iiririo is nssoointcd with *!28 pnrt of ~ihc~iphor~~s p i t onidla. 
(3) Piirtqiirntiori contniiis very littlo phos~ilintc. 
( 6 ) Soliib10 orgniiio nitrogon sliow~ n h i g h figuro thnn i!ic ulllorino in frcali urinc.soiletl flook. 
Tilo following figiircx diow tho porcctitngc of osli nntl R n d y riinttcr in n sclrctetl nunilar of rng-flcoks oooiprrcd with tho chlorine stiriitlnrd :- 



  His own suggestions woulcl b: (1) Cod to I& very finc. to Iw? pnssed through n fino sicvc of clclinitu sizc. (2) Inert mntcrinl (qunrtz or nnthrncitu or otlicr inntcrinl) to Im fincr thnn Cirmpreclon's inntcrinl nnd t o 1 ~' of n dcfinitc ~i z e . (3) Adoption of n uniform method of henting. ix.. mulllo or Bunwn. (The tc1ii~wrn111ru of coking should nlso be studied,) (4) Coking in n reducing iitmosphcre. ( 5 ) Soinc morc dcfinitc IIICIIIIY of nicnsuring the cohrrcncc of coke-it lint1 1wcn suggcstctl that ii w i g h t of 2 kilos. should Lc gently plncecl upon tlic button iiritl the crushing poacr would bc inucli morc unifornily incnsurctl by Chis wng thnn by ircswrc oI tho fingcrs. (61 To consider whcthrr the resu1!s should lm cspreswcl in larccntngc or in times the we~ght of conl. 


FlO. 1 .

 1 \\'liut w u dutitrinino iH tho ninoiirit of coniprcsrion ~intlurgono by tho #kin undcr n ccbrteiri lond, wliicli inlist be xo chosen thnt it tloos not eiiiiso rqitnrs. Tliero WIIB howercr no clungcr of thiH in nu of our oxpcrinicnts. ~n our iippiirntus tlin lonil itc ciiutrihocl over n section of onu tqirurtr c u n t i ~~t r c , tho c l i i ~~~~c t o r of the circultir jirws boing 1.128 om. 1 ho nincliinu thus intlicntus tiircct.ly tho specifio loncl or stms 11 untler~onu by tho diin. T~II: lottor is cornprcsscrl froni its originnl tliickncas 1, to n ncw thickness I,, tho relntivo compression this being X=l,-I, -I1 Wo proposc to rcfcr to tlio nunibcr E, dcfincd by tlio oqunt,ion E= + ns tho nvorncn ronistnnt!o of t l i ~ skin to coninrcssion oiidrr tho ntross p." It inny bc tnkcn ns n incusuro hf t,ho firnines8 of tlic fikin.* 




  Fig. TI. sliora diiigri~~~ii~~uticnlly tho olicct of tiuio on tho coriiprcssion of n liniotl skiii. It will I)o F C O ~ thnt nftor tlireu minutes over 00 por cont. of tho finiil conipruwion nt 20 niinutes wns rcnclicrl. A ~niicli Inrpr puriod tlian twonty ininutos cuiinot Iw tukcn, owing to tho grndunl drying of tho skin.\\'bun tliu proxsuro i H roloasutl froni tlic skin. thsticity will twit1 to rustorc it to its forniur nliiilie nncl tliicknoss. If this is dono in uir it will rusiilt in w r y gently incrunniiig t l ~u surfncos of contnct botcvccn witor ( a c t sliiii film) 11nt1 nir, nntl will thoruforu bu vury niiicli tippowtl by forccs of cnpillnrity, In ortlur t o nvoid tliis, t.liu osIierinionts intist bn cnrrind out iriitlur witor. \Yo thcruforo now icrforni ~I I our uqariniunts on reailiunuy iiiidar wutcr. f i i coni-pcusYion os]wriincnts it is olso et~rant.n~uous to work in thin itinnncr, ILR tliu flow froni tliu skin is tliurcbg fniditntetl tint1 surfucu ufiuctx guriercillv uliniirintctl. Tho find ro~ults uru Iiowuvur not atiuutod n~~procisl~lp. \ \ ' o tiiku this 11 tliu aklu wuru ~iurfuctiy clndtla k: auultl bu tile I I I I I ~I I ~I I H of eluntlclty. 




  ciit. tho vnluss of 1 . : iiru ~rlil~roxiniotuly liiic.ir fiinctions o f tliu htrnsw. Lr., I< cnir be ui~prorintntcl~v oxprussutl irs tr function (if tliu lond 11 by an cqiintion of tho forni in wliicli n und b iiro oonntnntr. 'I'iiblos 2 to 11 contain tliu rusultn of iiuniuroiiR os~wriniciitx on liincd, pilorod, wid doliniotl skins, unit Fig. 111. ropruscntn tlioso ~a n i u rusiilts grupliicully. At lowur Iircnwron tlitrii 1W grains p r sq. tin. tliu vehros of E U H I I U I I ~ full otl nioro ra iidly tliirn corrurcpontln to tliu niuililu ~iiiurtr roliition. \lowuver wu nccqit tliu viuw tlint tliusu rcaulta aru vitiotutl by Tlic resilicncu IL wrs tlion culculntcd. 13 =np+b WOOD, SASD AND LAWV-DETE~;\rrrrATIoN OF FALLING OF SKIN, $C. 




  In the l h f t Rcglilnt ions of tho Lixnl Covcriiiiicnt Bonrd,Scctiori 1 (1)of tlicRagFlock Act, 19l1,~crcncI:-"Article 1. Flock slinll IN cleciiicd t o cniiforui to tho stnnclnrd of clcnnlincse fnr the purjioecs of Sulmcction (1) of Srction (1) of tlic Act. when tlic niiioiint of solublu t!hlorinc. in t Iic form of cliloriclcs rciiiorcd by t horoirgli wnshiiig with cliatillecl w t c r nt n tcni~rrnlurc not cscccdiiig 25' ccritigrnclc froin not lcse thnn 40 grniiimcs of n well. iniurtl sninplc of Ilttck, clcws not c s c c ~d 30 pnrts of cliloriiio in 100,OOO parts of the. flock." The chlorine s!nnclnrd i j liiiscd up011 the fnct tlint huinnn urinc nnd pcrdpirat ion cmtniii consitlernble nnioiiiite of chlorides. '1:liis fuct i j sliowii in the follo\ving nnn1ysc.s. 50 g r i m of n \veil wndicc! and dried rng-flock wero niixcd with 5 0.0. of urinc. h \VOOIII:II vest previously sonkrd in perspirntion, cnuncd by vigorous eacreisc, wns tnkeii for n C O l l l J l U ~~% ~l l hnwd upon t hc clilorinc figurc. Parts in 1 0 0 . ~ pnrts of nintcrin1:-Clilorlac . . . . . . . . . . . . . . . . . . . . 


Dr. lh~ss, in

  replying, snicl 110 hntl not tried retort carbon. though hc rccogriisecl thut it. WBN R mnterinl thnt could prolmbly 110 obtninetl of very uniform composition and constant properties ; in wing unthrncite hc hnrl hnd i n his mind the facts thnt it wiis n substnncc of similur nature to thc conls of poor coking t unlity whiclr it would bo sought in nctunl prnctict: to hind, 



i w t l thut high-c griitlc nnthrncitcs probiildy cliffcrcd little in voliitilc~ matter, nnh, nnd physiriil properties from o m iinothcr. J'crhiips, howcvcr. it would bc ~vcll t.J specify n pnrticnhi niithrneitr

  , nntl in this rcspcct stnnclnrdisu thc test ns firr ns priicticriblc. TIicro wns no cloubt t h t when slurti wns used the nr11 of t.ho conl was un irn~~ort;trit factor, for hu lincl over iintl over iignin fonncl thut hy ntltling to II con1 n qiinntity of its own nsh its nppnrent iigglutinriti~~g power, ns tested Iiy siind, wnq iacrunscd. Ho hcul not found thnt tho tiwo of coking, with nnthriicitc 11s inort ~nntcrinl, 



nt lenst, h i d n i i w h cffcct on

  

tho r u d t : cvon such tlilferenwa 
iis butsccn 1% i ~n t l 20 minutes protlucctl no

  scrisible cffcct. 110 thouglit thnt ~ierhnps Mr. Smith's cs crioncu in this respcct nrow froin tliu nfio of n mumu. d i u ~jirnscii biirner siirroiinc~et~ t ~i o criiciblo with n reducing. or n t l c n ~t non-ositlising iitnior;. phcre, ahilHt tho ntinoep1:oro in tho iniifllo wus iis 11 riilu strongly osiclisioy. No doiibt II rcilricing ntmowplrrru ~1 s tlouir~iblo for t h o tcst, but it WIB q~~estioni~blo ivhctlier tlio ncltlitioniil liiboiir i w t i the ~~cltlitionnl coking reqniretl to nttiiin the rcqirisito tuinpcriiturc, inrolvutl in Nr, Smith's suggestion 



of pckiiig in cl~nrcni~l, voro roniunuriitiru. I t must bo roincnilicrerl that wo woru not niccixiiring hcru ii qtiiintity susco~~tiblo of nccnriito ~~~~~n o r i c r ~l tlotcrminiition, lnit scolting nn II qxoxiniiitu niucisuro of tliu buhuvioiir of u cou~ on tilo inrtustrinl scii~e undor cont~itioiis u ~i i c ~i no Inborntory tust coultl cstrotly iaiitoto. Onu circunistiinco iiiantionutl by 3lr. Smith wiis untloiibtc!tlly of inqiortuncc, nomoly tho sire of tho pnrticles. Antliracite wus not 80 denso ns snnd, nnd tho toncloncy to 
irregulnr distribution would hcnco bo less with nnthrncite thnn with snnd, b u t opnrt from tlint the hnrrlricss of tho coku sccmcd to clepcnd groutly on tho sizc of thu pnrticles both of coking nntl of non-coking constitiwit of tho mixture ; lie wns oxpcri- mcntiny furtlicr on this, nncl nt the inoinciit wna inclined to sirggcst thnt both constituents shoiild bc griiclccl bctrccn n rnillirnctru nnd Iinlf-niillimctrc siorc. A s to tho motlo of rtp~ilici~tion of prcssurr, he had

  
	found u i t h nnthr~icito
	thnt testing with tho fingcr WIS quito sirfficicnt for dis-
	tinction. Hc ~voultl be w r y silling to c s ~i c r i m c ~~t

on tho vnrioiis suggestions thnt I i i h Iiccn mndc. itnci roport to R Iiiturc mcctiiig. \W 11 rcfcrcncc t o thc

  
	C'hnirmnn's
	runinrks on the riirintions in results of clctcrininntions of
	rolntilu mntter

ennsetl by vnriiitions in gas prcssuro, if the tiiinoiisions of tho fltuno wcrc ntljn~tctf for cnch oxlieri- nient in the wny sngpatccl by tho Coiil-Aiii11~sis Coinniittco of t 110 Anicricnn Clicmicnl Society, the difficulty woiiltl ho ovcrconic, arid concortliint cletcrininntions obtninctl. Nottingham Section. Ncctiiig lid3 ti1 .VulliwJh(iut. 011 Il'cdncadoy, Jltrrcli 19Ih. l!ll:L - NIL S. n. TIlOT>IAS I S TIIE CIIAIR. - 'J'H E QL'ASTITATI V15 J>ETICltM ISA'I'IOS OF THE F;iI,LISG OF SKIS 1S TIIE I'UERJSC: Olt l%:I'HSG I'KOCESS. I'A11T 11. UP JOSEI'II T. WOOD, I I E S B P J. S. SASD, ASD DOUQLAS J. LAM'. 111 n foriner pupcr (this Jonrn., llnrch ISth, 191%) wo gi~vo ill1 account 01 IIII np~innitirs wliicli w u inny dcscribo us R pueronietor

  for tho in(fiiriiiwnei1t of tho iinioiint of cluplction which skins undergo ill tiiu procum of pucring. 



puercd , Fro. 3. I 1000 SLW: 300,-/!f! - 1 1'ucn.d 2 1.

  by tlivicltng tho diffcrcncc ticttvccn E n t 200 nntl E n t 100 ~r m n . pop sq, cni. by 100. Wo niny sny thnt for o linicd sliccp-skin E mcnsurcrl untlor n lontf of 100 grnis. por sq. cin. npprosimntcs to n little moro tlinn 400 grnis. pcr sq. cni., for R wcll-puerod shccp-skin irnrlcr tho tmniu conditions to 170 grms. pcr sq. cni. For n dclimctl shec skin, E mcnsiircd under tlieso conclitions is rrsiinlly slightL lower thnn for n pilored skin. Tho rnlucs of b for n 


	3	
	6 6.7,8	*,

I Lll;:cll o cdintln Slieup-shin jelly " (Tiiblc 51 !Tnblc 3) (Tnblc 41 i'L'lIblo lo) ITII~IO ij (Tnblc 11) 0"I'ibles 7 8, 0) shccp.skin usunlly vnry bctwecn nbout 20 nnd GO grms. cr sq. cm. itccording

  to t h u ninount of piicrinq tlic skin Ens rindorgono, for n limed skin they iisunlly lib botwecn 



200 nntl 400 grms. pcr sq. CIII., nncl for n dcli~ncd &in bctwccn 60 nncl 100 Frmr. per sq

  . rni. 


	Professor Proctcr has suggobtcd to us tlint tho co111-
	prossion of tho skin m y bc dctorniincd bv n law to t l , ~ cficct tlint tlic n n i o ~~n t of intcr~ibriIInry ivutcr cxlicllctl
	bv cnch incjcasc of prcsniiru will npprosiiiinto t o n uniforni
	f;oport.ion ( p ~ ~rcentagc) of tlin roinnining v o l ~~n i c

Twetily per cent. (ulroul) gcldrc. jelly eel lelwcen dice of truehitie (%minute interwla).

  
	4.24 4.24 +54 4-84 4.24 4.24	4.18 +ii 3.80 3.30 2% 3.01 0.405 4.25 0.0142 4.24 0.0307 4.24 0.0825 4-20 0.200 0.204	705 050 010 600 r10 $30	per cent. 100 loo 100 05 81 -	GO 100 200 500 100	2.40 2.40 2-50 2.40 1.8$	1.50 1.32 1-17 1.07 1.13	per cenc. 11.5 7.4 --0.504 530 -1.00 0.365 141 1-10 0.400 217 0.520 385 -1.23 0.400 250 13.4
						4.475 4.475 4.415 4.476 4.416 4.415 4.475		4.415 4.305 4.255 4.185 4.005 3-085 3.000
	0 6 10 15	o m 2.25 2.0. 1-84						
	20 30 50 75 100 200 300 400 600	1.71 1.00 1.40 1.33 1.24 1.01 0.02 0.82 0.00						

0,1734 0.348 0.3030 0.3523 0.3040 0.4470 04OWJ 0.6SOJ 0.0170 o.osoa 0.7368 0.0510 28.83 42.50 40.51 60.78 70.15 111.0 151.1 185.5 :1234 690.1 077.0 .wo.s 00 30 40 80 00 70 80 00 100 200 600 loo 4.80 4-30 4-30 3.00

  
	4.03 4.88 5.04	4-14 4.00 4.11
	4.77 4.82 4-06 4.JB 4-49 G*4U	8.87 3.m 3.44 3.41 2.00 8.

38 4.80 1.34 0 b 10 It 20 30 60 75 100 2o(I 300 400 2.60 1.08 1.74 I .to 1.44 1.34 l.1U 1.00 0-08 (1.85 0.70 0.47

  

TABLE 8 . Puered roan. Ttoctit!i per cent. gclafin jcily (anolhcr Rample of gelofin). I 10 20 50 100 200 300 -TABLE 0 . Limed ahccp-akin.

 80 

TABLE 2 . Puered 8?l#?Cp-8kiii. Lnnd in prtnn. em* E x Load In

 2 

TABLE 3 . Roan puered iii arlijcial bale. Originul thickiieaa I=?(W. I' I I* I I TAIJLE 10. Liined eiieep-akin, fi diflercitf portion tukcn for caclr TABLE 4. 1tonn pvered. Ciigiirat IhickncRb I, = 2'50 1n.m.

 3 
	A	]	E
		I	

363 810 308 872 316 Y4G 420 020 800 18rd - TAULE 11. Lirried akecp-81.in, all presaiirea 011 8ot11e porlioti.

  
	I	
	0.003	510
	0.144 0.210 0.310	431 W i 839
	0.370 0.m; n m nmo 1 3000 1176 1114 m o

Dcliined aheepaki~r, under tcder. DtscussIos.

  pointod out thnt cliffcront rncchnriicnl tosts for cluo ofton yicltlod different rcaults. Thus hc had known cises wlrero n gliru which wns found strongor thnn nnothor by tho shot teat gnrc n wcnkcr joint thnii tho othnr. 


	3Ir. J

-JIr. S. R. TnorariS suggested thnt the nuthi>rs' nicthod of tostino, might provo usoful in the cxniiiinntion of glue nrid goIntia, \c.hich n t Iirosent were gcnornllp jiirlgccl hy tho porcontngo of w t c r tlioy wcro cnpnblo of nl~sorbing. hfr. C. E. B. %I\I~RRIXAS inquircd d i n t would IJC tho rosult of tho tests if cnrriod out in n rnciiuiii. 3Ir. J. H. n U S F D l i D 
. 11. \VILKIE inquired whnt wns tho perccntngo orror of

  tho tostp. Jlr. S. J. PXSTECOST inquired whnt wns tho offcct of oil nnd gronso on tho inochnnicnl propcrtics of tho skin. hlr. J. T. \\~ooD, in roply, Enid that beyond cnusing rapid ovnporntion of tlio wnter coiitniiiod in it tho cff(*ct of plncing a pucrcd skin in n vncuum woiild IN slight. Hs hnd, howovor. snggostotl iuoring in vncuo 



, nR this w o u ~ be fnvotirn~o

  to t~ic! t~olJotion of tho sltiii. It Jvtia not poptiiblu t o obtain oxrict tluplicntos of niiy tost, RIIICO tho toxt inlist nocossnrily bo nirrtlo on tlifforont pirtn of tho skin. Adjncciit Iiioccs did not cliffor inoro tliirii 



n fow per cont., tho third flgnro of E boinq irnrolinblo. Nntornl flit in a shoup-skin in sonio rnsos nddcd much to its thickncar, nnd car0 must b tukoii in mlooting tost piecos wlicru t!~c fnt wns normal. I n n puorocl skin tho firt wns sot frcc nnd thc offoot wns nogligiblo. 
Yorkshire Section. Jfecfing held at the Ilolel Jlelropolc, Leeda, on Jlondoy, Jfarch lorh, 1913. PROF. A. CJ. QREES IS TltE CltAtR.

  Tlic uso of uiiwnslicd rsgs for tlic riinnufnctiirr of flock lins cniiscd disquiet for ymrs pnst, mid tlic I.ocnl Go\-crnuient Bonrd lins nt lnst tnkcri nction in tho slinpo of the llng Flock Act of 101 1. It scciii~ scnrccl?;mxlible tlint flock inndo froin filthy rngs, tlic reinnants of cnst-oIT clothing nncl strips of old c n r p t , which niny hnvc Imm picked out. froin n!fuse Iicrrpr," t o 1 


	-
	RAG FLOCK AXD THE CHLORIXE STAXDARD OF PURITY.

D Y F. w. I~ICII.\RDSOS ASD A. J A F F ~. 
1 8 ~' Dr. A. Xcwsliolnic's wortla, shoiiltl, without nny clransing otlic-r than n nicrc shnlting

  , furnish flock for tho stiilfiirg of ninttreaws nnd cuahions.Professor X2ttnIl nritI Dr. GrnIioni Siiiitli Iinvc wisely clcciclccl tlint it. woiilti bc inipmcticnlilc to cstnlilish n l)netcriologicnl stnncliircl of purity " (LCLB. llcport on Rng Flock, Xcw , 



Scric-s, So. 25, 1910, 1111. 27 to 29.)

  Ordinnry roiicl dust teeins with microlxd, ninny of thcsc of t h e coli spccics, nnd it is not eo iiiucli this dust but filth. from the huninii iwrsoii which oiic B islics t o detect in rng flock.