Journal of Industrial;
Engineering Chemistry
Published b y T H E A M E R I C A N C H E M I C A L S O C I E T Y
AT 8ASTON, PA.
Volume XI D EC EM B ER 1, 1919 , No. 12
H. E . B a r n a r d H . K . Be n s o n
Editor: C H A R L E S H. H E R T Y Advertising Manager: G . W . N o t t
A D V IS O R Y B O A R D
F. K . C a a i e r o n B. C . H e s s e A . D . L i t t l e , A . V . H. Mory
P u b lish e d m o n th ly . S u b s c rip tio n p ric e to n o n -m em b ers of th e A m e ric a n C h em ica l S o c ie ty , $6.00 y e a rly ; single copy, 60 c cn ts
P rice p e r single copy to A m e ric a n C h em ical S o ciety m em bers, 50 c en ts. F o reig n p o stag e , sev e n ty -fiv e c en ts, C a n a d a , C iib a a n d M exico ex cep ted E n te r e d as Seco n d -class M a tt e r D e ce m b e r 19, 1908, a t th e Post-O ffice a t E a s to n , P a ., u n d e r th e A c t of M a rc h 3, 1879 • i A c c e p ta n c e fo r m ailin g a t special ra te of p o stag e p ro v id e d fo r in Sectio n 1103, A c t of O c to b er 3. 1917. a u th o riz e d J u ly 13, 1918. .
A ll co m m u n ica tio n s sh ou ld be sent to T he Journal oi Industrial and E n g in eerin g C hem istry.
T e le p h o n e: V anderbilt 1930 Cable A ddress: J iech em 35 E ast 41st S treet, N ew York City
S u b scrip tio n s and c la im s lor lo st co p ies should be referred to Charles L. P arsons, 17 0 9 G S treet, N. W., W ashington, D. C.
Es c h k n b a c h Pr in t in g Co m p a n y, Ea s t o n, Pa.
TABLE OF CONTENTS Ee it o r ia l s:
i A M ission, a N ear Failure, and U ltim ate Success. 1102
T h e B a ttle Is O n ... 1103
H o t A ir— B u t W h y ? ... ... 1104
A G ood S ig n ... 1104
Co n t r ibu tio n s from th e Ch em ica l Wa r f a r e Se r v ic e, U: S. A .: Anti-D im m ing Com positions for Use in the Gas M ask. P. W . C arleton ... 1105
Anti-D im m ing Preparations for G as M asks. H arry N . Holmes, F . F. Jew ett, G lad ys Leavell, Dortha B ailey and E d n a S h a v e r . ... 1111
Or ig in a l Pa p e r s: Ph thalic A nhydride. II— T h e M elting Point of Pure P h thalic A nhydride. T h e System : Phthalic A n h yd rid e-P lith alic A cid. K . P . M on roe... 1116
P h thalic Anhydride. I l l — T h e System : . Naph- th alen e-P h tlialic Anhydride. K . P. M onroe 1119 H eat of Reaction of Am m onia Oxidation. G u y B. T a y lo r ... 1121
O xidation in the M anu facture of T N T . A lbert S. E a s tm a n ... ... Studies on the N itrotoluenes. I l l — B inary System s of the Com ponents />-Nitrotoluene, 1,2,4-Dimtro- toluene, 1,2,4,6-Trinitrotoluene. James M . Bell and Charles H- H erty, J r... Studies 011 the N itrotoluenes. IV — T h e Three-Com ponent S y stem : ^-Nitrotoluene, 1,2,4-Dinitrotoluene, 1,2,4,6-Trinitrotolueue. James M . B ell and Charles H . Hei-ty, J r... ; ... 112S Paracym ene. I l l — Preparation of 2-Chloro-5,6- Dinitrocym ene. H . A . Lubs and R . C . Y o u n g ... 1130
T h e C arboh ydrates of Fresh and D ehydrated Vege tables. K . George F a lk ... 1133
P ossibility of Com m ercial U tilization of Tom ato Seed ' and G rape Seed. J. II. Sh rad er... 1134
La b o r a t o r y a n d Pl a n t: T h e A pplication of R o tatin g Reductors in the D e term ination of Iron. W alter S c o tt... 1135
T h e Perm anganate M ethod for Copper. Louis F. C la rk ... 113S T h e Use of N ickel Crucibles for the J. Lawrence Sm ith Fusion in Determ ining Soil Potassium. Seth S. W a lk e r ... H
39
Ad d r e sse s an d Co n t r ibu ted Ar t ic l e s: Chem icals Received b y the Bureau of Chem istry during the W ar. H . E . B u c ... 1140R eport on the Production of Synth etic Organic Chem icals in the Research L aboratory of the Eastm an K o d a k Com pany for the Y e a r 1918-1919. C. E. K . M e es ... 114 1 1124 1124 T h e Exam ination of the College Trained Chemist-for. Governm ent Service. W illiam J. C o t t o n ., ... 1142
Bibliography on the Use of "C upferron ” as a Q uantita tive Reagent. S. A . B r a le y : ... ... .... 1144
Sym posium on Re f r a c t o r ie s: , T h e W ork of the Technical Division of the R efrac tories M anufacturers’ Association. R . M . Howe. 1145 T h e Selection of Refractories for Industrial Furnaces. W . F . R o ch ow ... . 1146
Interesting F acts Concerning Refractories in the Iron and Steel Industry. C . E . N esbitt and M . L. B ell* 1149 Superior Refractories. Ross C. P u r d y ... 1151
R efractory Problems of the G as Industry. W . H.. Fulweiler and J. H. Taussig. . . . ... ;... 1153
Foreign In d u str ia l Ne w s: Therm alene; Platinum ; Electrical Precipitation of T ar Fog; M agnetic. M ethod for T esting Ferrous , M etals; Tanning M aterial Deposits; L actic Acid; M aking Concrete Blocks; Autom atic Stokers; T h e H öchst D yew orks; Tim e Lim it Fuses; E lectrically , H eated Boilers; Case-H ardening; Ozokerite; D e term ination of L ight H ydrocarbons in F at; Im port Prohibition; Alum inates of Lim e as Cem ent M a terial; N ew Indirect, U nit for Industrial Lighting; . Paper Thread; Luminous Paints; Coal from Sulfite L y e ; Iron-N ickel A lloys; Alum inum Sheet and Sections; German Chem icals... 1157
Scie n t if ic So c ie t ie s: , Standard M ethods for the Sam pling and Analysis of Commercial F ats and Oils; Lectures a t W est Point and Annapolis under the Auspices of the American. Chem ical Society; Am erican Institute of Chemical Engineers; Societa di C h im icaln d u striale. . . v . 1161 Notes an d Co r r esp o n d en c e: Some R em arks on Standard M ethods of Soap Analysis; T w o Letters on the T reatm ent of Low-Grade N ickel Ores; A Selective B ibliography on W aste Utilization as Affected b y the W ar; Specifications for R eagents; Platinum T hefts; Chem ical W arfare Service; Problems and M ethods in Agricultural ' Research— Correction ... : . . 1169
Wash in gto n Le t t e r... 1172
In d u st r ia l No t e s ... .117 4 Per so n a l No t e s. ...- ... : 1176
Ob it u a r y... 1177
Gover n m en t Pu b l ic a t io n s. — . . ... 1178
B o o k R e v ie w s , , \ ... . ri8 i New Pu blica tio n s'. . . . 1185
Ma r k e t Re p o r t... 1184
Au th or In e e x... 1185
Su bje c t In d e x... 1190
IIO2 T E E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol. n , No. 12
EDITORIALS
A MISSION, A NEAR FAILURE, AND ULTIMATE SUCCESS W e have had a h oliday; our readers have had a tw o m onths’ relief from the usual outpouring in this section of the J o u r n a l , w hile we h ave had op p o rtu n ity to get a broader vision b y actual presence on the scenes where so v ita l a ch ap ter of the w orld’s h istory has been w ritten. B u t it is good to be back, b ack in th a t land of lands w hich we call our own.
W h y did we forsake our post? L ast A u gu st the shortage of v a t dyes becam e v e ry acute; A m erican m anufacturers of dyes were not y e t read y to supply th e home m arket, so th e W ar T rad e B oard Section of the D ep artm ent of S ta te decided to gran t licenses for im ports of v a t dyes of enem y origin in q uantities sufficient to cover consum ers’ needs for six m onths.
T h e experience of France, Belgium , and Ita ly in se
curing lim ited supplies of G erm an dyes suggested th a t A m erican consumers m ight also be supplied, possibly through th e C om m ittee on O rganization of th e R ep ar
ations Com m ission and from th e stocks of dyes being held in G erm an y to meet the term s of th e T re a ty of Peace. U nder A nn ex V I of the T re a ty th e Allies are given an option to b u y 50 per cent of th e existing stocks of dyes w ithin six ty days after the procla
m ation of the ratification of th e T re a ty , and for five years th ereafter w ill h ave an option on 25 per cent of th e to ta l am ount m anufactured, th e option to be exercised a t six-month intervals.
W ith th e ap p roval of President W ilson and upon the solicitation of the president of th e C hem ical F ou n da
tion,- In c., we undertook the w ork of ascertaining in w h at m anner, and b y w h at m achinery this six m onths’ supply could be obtained, fu lly conscious of th e irony of the situation. On the d a y of arrival a t P aris an im p ortan t interallied conference was being held in London, and there it was decided to in vite the G erm an m anufacturers to a conference at Versailles to arrange for a partial release of stocks. If this proposal w as agreed to, France, B elgium , and Ita ly were to w ithdraw not more than 2200 tons of dyes, w ith the fu rth er provision th a t not m ore th an 30 per cent of th e 50 per cen t of each color was to be w ith draw n. T h e U nited S tates and G reat B ritain were to h ave th e privilege of w ithdraw ing not more than 1500 ton s each, under the sam e conditions, thus giving the righ t to not more th an 20.45 Per cent of th e 5°
per cent of each color. L ater, in order to insure the p articipation of the Germ ans in th e conference, for it was not a m atter of tre a ty enforcem ent b u t of jo in t agreem ent, it was decided to offer to th e Germ ans the release for free sale, from their h alf of the stocks, of a q u a n tity corresponding to th e kind and am ount of each dye tak en b y the Allies. T h e proposal brought the Germ ans to Versailles for a prelim inary conference w ith representatives of the Allies on O ctober
2, 1919.
A few days before the conference too k place inform a
tion as to the to ta l poundage required by^our con
sum ers was cabled. It was im m ed iately eviden t th a t on ly ab out 30 per cent of these needs could be provided for under our percentage share of each dye. T o supplem ent this and to com plete the block it was determ ined to seek a direct offer from the Germ ans to su p p ly the balance from their released stocks, or b y im m ediate m anufacture.
On O ctober 4, 1919, th e conference was held at Versailles, M. M auclere, of France, presiding for the A llies, Herr D r. C . von W einberg, the present head of the k artel acting as chairm an of the eight representa
tiv es in the G erm an group. T h e outcom e was satis
fa cto ry to all parties concerned. Im m ed iately after adjournm ent we held a personal conference w ith D r. von W einberg and secured from him, after his consultation w ith his associates, an offer to com plete A m erican needs at prices for each d ye to be reckoned b y dividing b y four, in th e case of v a t dyes, th e price per kilo in m arks on th e in v en to ry list of A u gu st 15, 1919- T h e quotien t represented A m erican dollars per kilo. In the case of general colors the divisor was to be five.
W ith this proposition we returned to Paris, hap p y in th e th ou gh t th a t the mission which had tak en us to E urope was finished. T o com plete th e tran saction there rem ained only the tran sm ittal of the proposals to the consumers a t home, and, if th ey m et approval, to have a represen tative leave A m erica a t once, pro
vided w ith purchasing au th o rity and funds.
A s q u ick ly as possible a cable was prepared giving the details. W hile it was being typ e w ritte n a m es
senger handed us a cable containing th e inform ation th a t on O ctober first the allocation cards h ad been given out to consum ers w ith auth orization to im port through an y com m ercial channel.
T h e sp lit am ong consum ers as to m ethods of im p o rtatio n brought u tter confusion into the situation, and from a quarter least expected, for we had been to ld before leavin g home th a t the v a t dye consumers w ould be organized into an association w hich would purchase th e dyes, and th a t th e dyes w ould be handled as a block proposition. W e could not tell how great w ould be the split am ong consum ers or on w h at basis we could fu rth er w ork. One th in g was certain:
D e la y in receipt of the dyes w ould in e v ita b ly ensue so far as th e consum ers were concerned.
A s the days passed the situation seemed to become worse, th ou gh m eanwhile the T ex tile A lliance had been designated as th e agency th rou gh w hich the reparation dyes w ould be im ported. W e g av e up hope and started th e jou rn ey home bluer th an th e purest indan- threne.
A t th e end of the th irteen -d ay v o y ag e we were met at th e gang p lan k of the ship b y a rep resen tative of the T ex tile A lliance, and received the news th a t harm ony and u n iform ity again prevailed, th a t assignm ents of allocation certificates to G erm an im portin g agencies had been cancelled b y consum ers, and th a t th e y had united
Dec., 1919 T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y 1x03 upon th e T extile A lliance as the sole medium of im
portation. Som e greeting th at! T here had been unexpected and unnecessary delay, but there could now be no doubt of an early and successful term ination of the whole m atter. A nd so it turn ed out, for in a few days a m eeting was held, as a result of w hich a message, w hich m ust h ave taxed th e ca p a city of the cables, was sent b y th e A lliance to its European representative, ordering the dyes.
THE BATTLE IS ON
“ Unless the spirit of independence is dead in the hearts of A m ericans, our people will never be satisfied until th e A m erican dye in d u stry has been developed to a p oin t where it can ta k e care of every Am erican need and stan d as a bu lw ark of reserve for any future conflicts in w hich our nation m ay be compelled to en gage.” T h is was th e rem ark we m ade to the vice president of th e T ex tile A lliance as we left the offices of the B adische A nilin und Soda F ab rik at Ludwig- shafen on O ctober 30. His in stan t agreem ent with the sentim ent, in words much more picturesque and em p h atic th an we had used, convinced us th a t we had read aright th e signs of th e tim es evidenced during th e tw o-hour in terview we had ju st had w ith the high officials of th a t greatest of all G erm an d ye m anufac
tu rin g establishm ents.
On the previous d ay we had had a ve ry pleasant m eeting at F ra n k fu rt w ith D r. C. von W einberg, the head of the G erm an d ye K a rte l, and were beginning to feel th a t after all m atters were shaping nicely.
W e proceeded to the Badische p lan t in a com fortable mood. B u t th e first few m om ents of th e interview w ith th e officials of th a t plan t brought out from D irector K rell th e volunteered inform ation th at the lines had broken a t home, th a t already he had in hand orders from ind ivid ual consum ers w ith auth ority from th e U nited States G overn m ent to ship through th eir A m erican agents to th e consumer. “ C o c k y ” is the on ly w ord to describe the attitu d e of the direc
tor. He had no desire to discuss any m atter in which we were interested, but w ith characteristic Germ an p sych o logy he endeavored at once to secure our assis
tan ce in persuading our G overnm ent th a t this whole m atter could and should be handled only through the A m erican agents of th e G erm an dye works. “ Y e s ,”
he said, “ W e are going to get b ack our old business in A m erica, and through the medium of our former agencies. T h is is the o n ly w a y it should be done, and th is is the w a y it w ill be done.” T h e rem ark was so illum in atin g th a t we asked him to repeat it, w hich he did.
T h ere we sat listening to this statem ent in the offices of th e chief p lan t of th a t great com bination of m anu
factu rers whose form er control of our dyestuff supplies had led vo n Bernstorff to suggest to the K aiser th a t th rou gh sh u ttin g off these supplies he could throw four million A m ericans out of em ploym ent; perhaps in the v e ry room where millions of dollars had been vo ted to corrupt A m erican industrial life; and near
the spot where tons of m aterial had been produced for poison gas b y whose d ead ly action m an y a gallan t doughboy had "gon e w e st” and now slept beneath French soil. Sm oke was pouring from all b u t tw o of the m any ta ll stacks of th a t establishm ent. The industrial war was on; the words of D irector K rell left no doubt about th at.
T h e sam e suprem e confidence characterized the industrial G erm an as had been recorded of th e m ilitary G erm an in his first advan ce through B elgium , the sam e u tter contem pt shown of A m erican c a p a city to do things as was shown during 1917. B u t 1918 showed th a t the G erm an had missed his guess and we m ake the prediction th a t he has missed again. O nly one th in g is needed to insure th e correctness of th a t prediction, nam ely, th a t the mass of our people understand ju st w hat the situation is. T o th a t understanding we are confident the A m erican press will continue to co n trib ute, as it has alread y done so splen didly during the past three years. T h a t understanding w ill reflect itself in sym p ath etic p rotective legislation and tim e w ill do the rest, for the A m erican chem ist needs on ly tim e to forge th e missing links in th e chain of a com plete self-sustained A m erican dye industry.
In the com m ercial struggle th a t is now on, the w ay is not plain sailing for the G erm an m anufacturer. In addition to w h at A m ericans have already accom plished and are determ ined to com plete, the G erm an faces a w inter in which the coal supply is destined to prove a more serious obstacle to contend w ith th an was the food problem resulting from the blockade. T ran sp ortation problem s are also ve ry acute, though the R hine will furnish th e n atu ral transportation for dyes to R o tte r
dam if th e w inter rains come early enough to restore the volum e of w ater in the river, now so low as to re
quire ligh t loadin g of the steam ers and barges which carry so much of G erm an com merce. F in a lly , th e G erm an is b a d ly worried over th e situation created b y the seizure of those patents b y which he had th ro t
tled A m erican in d u stry for so m an y years. He signed the T r e a ty of Peace, agreeing th a t these seizures were valid, b u t already he is beginning to whine and to tr y carefu lly to m anufacture sentim ent against the splendid w ork in behalf of A m erican com m ercial freedom so courageously carried out, under the auth ority of Congress, b y the A lien P ro p erty C u s
todian.
In spite of these handicaps the G erm an dye m anu
facturer is strong to-d ay. H is p lan ts are even greater than before the w ar, the personnel of those p lan ts is p ractically in tact, large stores of m aterial are accum u
lated and he is determ ined to regain his m arkets.
I t would be foolish to belittle th e G erm an’s a b ility or his fighting strength, bu t in the lig h t of th e a c
com plishm ents of th e past four years, and indeed of the brilliant achievem ents during the short period of our absence, our mind turns b ack w ith suprem e confidence in the correctness of the prediction of th e Swiss pro
fessor who tw e n ty years ago said to us, “ T h e n atural house of the dye in d u stry is A m erica, and some d ay it will be th ere.” Speed the d ay, oh ye chem ists of Am erica!
1 1 0 4 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol. n , No.
HOT AIR— BUT W H Y?
Life has its surprises; and one of these w hich greeted our return to the editorial office was a mass of clip
pings setting forth in flaring headlines th e view s of M r. Irvin g A. Keene, of London, as to the present ve ry lim ited supplies of stocks of G erm an dyes, based upon a su rvey which he m ade during a Septem ber visit to th e G erm an dye plants.
H onesty compels the admission th a t a t first sight of these clippings we laughed h eartily, because of the memories of an evening spent w ith M r. Keene in Paris. A closer reading of the clippings, how ever, showed th a t th e m aterial had been put out b y the A m erican C ham ber of Com m erce in London, and had received its official sanction and endorsem ent.
Furtherm ore we learned y esterd a y th a t copies of th is m atter had been p u t into the hands of m em bers of the U. S. Senate, and th a t m uch im portance was attach ed to these view s.
T h e m atter had th us tak e n on a much more serious aspect th an we had ever dream ed possible. In the interest of tru th , let us narrate the sto ry of th a t ev e
ning in Paris.
W hile in L ondon on Septem ber 16 and 17 we had heard of a group of A m ericans in Berlin, representing the A m erican C ham ber of Com m erce. T h is was v e ry interesting. R etu rn in g to Paris, we looked up the Com m ercial A tta ch é of th e A m erican E m b assy to learn, if possible, more details about this pilgrim age.
T o our surprise we found th a t th e “ grou p” consisted of one man, M r. Irvin g A. K eene.
T h en on Septem ber 26, 1919, there appeared in the Paris edition of th e Chicago Tribune, under conspicuous headlines, a dispatch from Berlin, covering an in ter
view w ith M r. K eene, in which he set forth at length how lim ited was th e su p p ly of G erm an dye stocks, as based upon his personal su rvey, and how little prospect there was of the dum ping of G erm an dyes.
T h e in terview was extrem ely im p ortan t, if th e fa cts were correct, for th e lists of these stocks furnished b y the Germ ans them selves, and our know ledge of the exten t of licenses for th e sale of d aily o u tp u t granted by th e In terallied R hineland Com m ission, did not indicate an y such p a u city of stocks as M r. K eene proclaim ed. T h e inference was th a t if M r. K een e was correct in his estim ate, surreptitious leak age of these stocks was ta k in g place rap id ly. W e determ ined to in vestigate, to go into th e R hineland, to consult w ith the Com m issioners and to get th e fa cts through any available channel. W hile com pleting passport ar
rangem ents for th e trip , our C om m ercial A tta ch é inform ed us b y telephone th a t M r. K een e was in Paris. L ater in the d a y we were introduced to M r.
K een e, and after a few words of greetin g we in vited him to dinner th a t evening, for th e stated purpose of discussing his experiences in G erm an y. A t eight o’clock we dined at th e C afé B oeuf à la M ode.
M r. K eene was a deligh tfu l dinner com panion, bu t w ithin ten m inutes we were convinced th a t his view s ab out G erm an dye m atters were not w orth a tin k er’s dam . H ow ever, we w anted th a t opinion confirm ed b y positive and definite statem ents from
M r. Keene, so we sought b y m an y questions to draw him out. Space does not adm it of a detailed narration of th a t conversation, bu t all connected w ith the dye in d u stry can jud ge M r. K een e’s com petence b y tw o bits.
R ep lyin g to a request for details concerning dyes being m anufactured b y the B a ye r C om p an y, after som ew hat exhaustive efforts w ith generalities which had no m eaning, he finally ven tu red th e suggestion th a t th e com pany was m anufacturing some colors whose nam e sounded like “ algerole.”
H avin g com pleted the jou rn ey through th e lower R hine region w ith ou t eliciting a n y definite inform a
tion, we m oved w ith conversational steps higher up th e river in the hope th a t recollection of experiences there m ight be more definite. M an y stories were told, b u t again no definite d ata and no descrip
tion of plants visited. T h e evening was d raw ing to a close; we began to press m atters. T h e w ord “ B adische” had not been m entioned, so we asked: “ W h at about the B adische p lan t?” T h a t w as a strange word w hich brought forth no intelligent gleam . W e explained in d etail th e im portance of th a t p lan t in G erm an y’s d ye régim e and th e m anifold character of its products. Suddenly M r. K een e broke in and explained th a t th a t p lan t was over to the right, and there was a little railroad th a t ran off to it, b u t th a t he had passed the jun ction point and did not h ave tim e to go back when he learned of it. T h a t finished us.
W e didn’t know an yth in g about the ju n ction point, b u t we did know where M r. K een e got off as a dye expert, and how m uch reliance w as to be placed on his view s of th e statu s of the G erm an dye ind u stry.
H ow ever, we still w anted a definite statem en t about those stocks, so as we w alked up the R u e de R iv o li, we p u t a question so direct to M r. K eene it could not be evaded, and in rep ly he fra n k ly state d th a t he had gone through no w arehouses, as there w ould h ave been no use in it, for, as he explained, he w ould not h ave know n a dye from a soap box. T here, we had it at last!
A GOOD SIGN
One of the m ost jo y fu l sigh ts th a t greeted us on re
turn in g was a large sign conspicuously placed in one of the m ost crow ded portions of N ew Y o rk C ity , bear
ing th e inscription:
W A N T E D
1000 Me n f o rt h e Ch e m i c a l Wa r f a r e Se r v i c e En l i s t m e n tf o r On e o r Th r e e Ye a r s
T h a t sounded like business. E v id e n tly we are on the road to an A rm y w hich w ill be p rovided and equipped w ith all th a t is m odern in w ar d evelop
ments.
T h is feeling was strengthened b y the good news re
ceived in W ashington th a t it is th e opinion th a t m em bers of Congress are p ra c tic a lly unanim ous in their de
term ination th a t there should be a C hem ical W arfare S ervice as an independent u nit and provided w ith e very fa cility .
Dec.; 1919 . T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y 1 i o s
CONTRIBUTIONS FROM THE
CHEMICAL WARFARE SERVICE, U. 5 . A.
ANTI-DIMMING COMPOSITIONS FOR USE IN THE GAS M ASK1'2
B y P . W . C a r l e t o n R ec e iv e d A u g u st 9, 1919
A s long as the gases used in w arfare affected only the resp iratory organs, a gas m ask needed only to pro
tect those organs, and th e m ain question was one of absorbents. W hen lach rym ato ry gases were used th e eyes needed p rotection and the situation then becam e such th a t a com plete p rotective unit was necessary. W ith this enlarged function a gas mask necessarily becam e a more com plicated piece of ap
paratus. R esearches were undertaken b y the warring nations to sim plify and im prove th e masks. W hen th is cou n try entered the war, each nation had its own ty p e of m ask and the U nited States A rm y adopted the ty p e w hich th e E nglish were using.
Good vision was one of the m ost im portan t proper
ties of th e gas m ask. T h e follow ing d ata obtained by A . L. K eller indicate th a t a m ask seriously lim ited the field of vision of the wearer, and. show the im provem ent in th e later ty p e of mask. T h e masks named are: old S B R , an early model of th e m ask used b y the A m erican forces p rac tica lly entirely, although made in several styles closely resem bling one another; the old ty p e French m ask (Ma) used b y the French until the last year of th e w ar; th e newer A m erican mask (Tissot) m odeled on th e principle of the French Tissot mask. T h e to ta l w id th of th e field of vision, in de
grees, th e w idth of th a t p art of the field seen b y both eyes (binocular), and the exten t of the dow nw ard vision, also in degrees' from the horizontal, are shown in the follow ing tab le:
Ta b l e I — Fi e l d o f Vi s i o n a s Af f e c t e d b y Ga s Ma s k s T o t a l W id th B in o c u lar D o w n w ard
of V ision V ision Vision
D eg rees D egrees D egrees
O ld S B R M a s k ...* 60 50 30
F re n c h (M s )... 80 50 35 A k ro n T i s s o t... 120 50 40 N a k e d E y e ... 190 120 65
T h e field of vision w as, therefore, being enlarged in th e newer ty p e s of m ask, bu t restriction of the field of vision was not th e only w ay in which vision was lim ited. B ecause ordinary glass lenses were not safe and the sa fe ty glasses could not be m anufactured in sufficient q u a n tity on such short notice, lenses of cellu
loid had to be used. These scratched easily, thus m aking the vision poorer. E xperim ents conducted a t th e A m erican U n iversity E xperim ent Station showed th e effect of poorer defining pow er of eyepiece m aterials on efficient use of vision. R ifle sighting (not shooting w hich in volves other factors), color discrim ination and
1 T h e w o rk o u tlin e d in th is re p o r t w as c arrie d o u t e ith e r b y o r in co
o p e ra tio n w ith th e E y ep iece U n it of th e D efense S ectio n of th e R ese arch D iv isio n of th e C hem ical W arfa re Serv ice * at th e A m erican U n iv e rsity . T h is a rtic le h a s b een a p p ro v e d fo r p u b lic a tio n b y M ajo r-G e n eral W illiam I,. S ib e rt, D ire c to r of th e C h em ical W a rfa re Service, U . S. A.
8 T h e follow ing m en of th e E y e P iece U n it p a rtic ip a te d in th is w ork a n d each h a s c o n trib u te d to i t : F . F . B erg, H . K . C u m m in g s, K . F ly n n , W . S. H u g h e s, A. I,. K eller, L . W . N ic h o ls, C. N . R ic h a rd so n , I*. D . S m ith , G . W . W ilson, T . H . W oodside,
tests in volvin g coordination of vision and m otion showed th a t these functions were not seriously affected in good light b y decreased defining pow er of a lens until the lens had a defining power, as measured b y a reading chart, of about 40 per cent. Sim ilar experim ents at different degrees of low illum ination showed th a t in poor ligh t th e defining pow er of an eyepiece was v e ry im portan t, and one could not afford to sacrifice this at all. Since m uch work at the front was per
form ed at night obviously th e masks should be pro
vided >'ith a m aterial which would not scratch. As fast as possible, therefore, sa fe ty glass eyepieces were being m ade th e entire production for gas masks.
For a v e ry considerable tim e the most serious vision difficulty was not th a t of scratching the lens, or even the lim itation of the field of vision b y th e m ask, b u t rather the elim ination of vision b y the fogging or dim ming of th e lens b y droplets of m oisture condensing on the inside surface.
Before discussing the various solutions of this diffi
cu lty w hich were attem pted, it should be noted th a t th e conditions were not identical in the different typ e s of mask. In general, m asks m ay be divided into tw o classes, as follow s:
1— M asks h aving an un ventilated facepiece, such as th e English and Am erican box respirators.
2— M asks h aving a ven tilated facepiece, such as (a) the early French (M?) and the G erm an m asks in w hich the air entered and passed out through the same p ath, and (b) the T issot ty p e m asks in which th e air passed out b y a different path th an it entered.
T h e dim m ing problem of th e G erm an and early French (M2) masks resem bled th a t of the u n ven tilated masks more closely th an it did th a t of th e T isso t m asks.
T his was because the exhaled breath satu rated w ith m oisture passed through the same path, absorbent in cluded, as the air entered on inhalation so th a t th is p ath soon becam e saturated w ith m oisture and then the inhaled air becam e loaded w ith m oisture and could not evap orate it from the eyepieces.
T h e m asks used b y th e Am erican forces were un ventilated. T h e m oisture condensing on th e fab ric and lenses was due to evaporation from the eyes and skin plus any due to breathing into the facepiece, as when talk in g w hile w earing the mask. T h e am ount of m oisture thus distilled from th e face of an active man was v e ry appreciable. T h e large am ount of this w ater m ade it im possible to dry the atm osphere in the m ask and thus low er the dew -point so th a t no fogging of the lens could ta k e place. T h e early F rench (M 2) and G erm an m asks caused more m oisture to condense on the lenses th an did the E n glish or A m erican box respi
rators because in them th e lenses were affected b y the m oisture of the breath in addition to th a t evap orated from th e face and eyes. .
Since th e clouding of the eyepieces occurred because the tem perature of the lens was below the dew -point
n o 6 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol. u , No. 12 of th e atm osphere w ithin the m ask, prevention of
dim m ing could be accom plished (a) b y raising suffi
cien tly the tem perature of the lenses, (b) b y low ering the dew -point of th e atm osphere w ithin th e mask, (c) b y using a m aterial for th e lens whiich w ould absorb w ater, (d) b y th e use of such a m aterial th a t w ater con
densing on it w ould form a th in tran sparent film in stead of droplets. O b viously, com binations of these m ethods are possible. Follow ing a suggestion of Dr. A. B . Lam b an A m erican box respirator was modified b y D r. W . L . A rgo, who died a Lieuten an t in th e C hem ical W arfare Service, so th a t dim m ing did not occur, b y using a com bination of the first tw o m ethods m entioned above. T h is m ask was not de
veloped for production.
T h e last m ethod was the one used during th e war b y th e A m erican forces. T h e first m aterial intended to prevent clouding of the eyepieces was far from satis
fa cto ry , and its im provem en t was undertaken b y the A m erican U n iversity E xperim ent S tation and was only part of the problem of the betterm ent of th e vision properties of the m ask, a problem w hich was con
tin u ou sly shifting w ith change in style of m ask.
Som e of th e requirem ents w hich a satisfacto ry anti- dim m ing com position had to m eet were as follow s:
I t m ust be soluble in w ater and reduce the surface tension of w ater so th a t moisture would n ot form drops on the lens.
I t m ust be easy to apply.
Its method of application m ust be “ foolproof,” so th at, if possible, an unsuccessful application would be impossible.
One application of it m ust last a long tim e, several hours of consecutive use.
I t m ust function properly several days after its application.
I t should be put up in a convenient outfit w hich should have b u t few parts and should not be fit for other uses. O bviously the unit should be cheap.
M E T H O D S O F T E S T IN G
T h e final test of any com position was its use in m asks worn in a cold room. O ut of doors conditions were more severe a t th e sam e tem perature due to the wind, b u t as th e y were not reproducible the rooms were used for all bu t the large tests.
Several m achines were m ade to im itate m ask condi
tions, for instance, boxes h avin g w arm m oist air on one side of the eyepieces and cool air (or w ater) on the other. T hese devices were satisfacto ry for rough re
sults only. T h e y were used in testin g m oisture-ab- sorbing eyepiece m aterials, cellulose and gelatin.
T h e difficulty of reproducing d ata on consecutive tests and even a t different positions in the sam e test pointed to the non-uniform ity of m oisture conditions and flow of th e air at th e testin g positions. M an y attem p ts were made to elim inate this trouble. T w o m achines were built b y th e E astm an K o d a k C om pan y for testin g the gelatin eyepieces w hich it was develop
ing. T hese m achines were altered (one in R ochester, the other b y C. N. R ichardson in W ashington) and the final form s were identical in principle. T h e m aterials to be tested were held in holes in a disc w hich revolved slow ly so th a t each lens could be exam ined w ith the disc in m otion. W arm , moist air was on one side of the disc and cold air on the other. T h e tem peratures
were m aintained b y circulatin g th e air b y vacuum cleaner m otors, th e w arm air bubbling through w ater h eated to th e desired tem perature, and the cold air passing through coils of pipe in ice. T hese m achines were not satisfacto ry until th e y were modified to h ave the revo lvin g disc. A ll attem p ts to m ake a m achine capable of testin g several lenses a t once w hich operated b y holding the lenses statio n ary, and controllin g th e tem p eratu re and ve lo c ity of the air passing them gave variable results both for different positions in th e same run and for the same positions in different runs. It was necessary to h ave e v ery lens traverse th e same p ath to be su bject to identical conditions. W ith th is ty p e of m achine results were reproducible w ithin the variation of the m aterial being tested.
Because of the lack of a satisfacto ry m echanical test only a few such tests of anti-dim m ing com positions were made. M aterials show ing prom ise were given m ask tests b y an experienced squad at different tem peratures in cold storage room s.1 T h e men of th is squad deserve great credit for four m onths of tedious, disagreeable work. T here was considerable advan tage in h avin g such experienced men availab le for criticism of th e different m aterials w hich were tested as in this w a y different points of view were obtained. In these tests both the old French (M 2) and the A m erican box respirator (S B R ) m asks were used. T h e French m ask was preferred since it g ave a more severe te st of the m aterial and was more com fortable.
I t is im probable th a t th e m an test of these m aterials could be en tirely elim inated as th e p sych ological side of th eir use b y all sorts of men under w id ely varyin g conditions w ould require some experim ental stu d y.
A few large tests, perhaps one, w ould give th is inform a
tio n if a satisfacto ry m achine test were a va ila b le.2
T H E S E A R C H F O R A N A N T I- D IM M IN G C O M P O S IT IO N
T h e stu d y of anti-dim m ing com positions w as under
tak e n in cooperation w ith D r. H. M . Ittn er, of C olgate and C om p an y. E xperim en tal preparations were m ade in their lab oratories for a m onth or more until it was possible also to prepare sam ples a t th e A m erican U ni
v e rs ity E xperim ent Station. A ll testin g was done in W ashington.
One of th e early ideas, and one w hich was su g
gested b y m an y persons, was th a t th e tru e fu n ction of an anti-dim m ing com position was to clean th e lens, and th a t m oisture w ould condense as a tran sparen t film on such a surface. T h is was not th e case even w ith glass. I t is tru e th a t we did not go to extrem e lengths in cleaning th e surfaces of lenses b u t it w ould be im possible to guarantee clean surfaces for lenses of m asks being worn a t th e front.
T h e chief d ifficulty w ith the anti-dim m ing com posi
tion being m anufactured a t th a t tim e for the A rm y was th e danger of rubbing it all off th e lens. T h is
1 T h e C e n te r M a r k e t C old S to rag e C o m p a n y of W ash in g to n allow ed th e u se of its ro o m s fo r th is p u rp o se.
* A n a p p a r a t u s fo r th is p u rp o se is d e sc rib e d b y H . N . H o lm es in th e follow ing a rtic le . I f th is device w ere te s te d , u sin g g e la tin lenses in th e d ifferen t p o sitio n s, i t is n o t to b e d o u b te d t h a t th e re w o u ld be m a rk e d differences in th e c o n d itio n s a t d iffe re n t p o sitio n s, b u t t h a t does n o t m ean t h a t i t m ig h t n o t be u sefu l fo r te s tin g a n ti-d im m in g c o m p o sitio n s, if m an y te s ts w ere m ad e.
Dec., 1919 T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y 1107 preparation, called th e “ p a ste,” consisted of chalk,
w ater, glycerin, and soap. T h e chalk m ade it opaque, so th a t one was com pelled after placing some of it on th e lens to rub m ost of it off and clean the lens in so doing. T h e instructions for the use of this m aterial were printed on th e containers as follow s:
W ipe the inner surface of the eyepieces of the box respirator or sponge goggles until clean and dry. A p p ly a little of the composition from the tube to the cleaned surface, rub it in with the finger, then polish gently w ith a soft rag until the eyepiece is clear. D o not use the mask m aterial for polishing.
T h e criticism of this com position was not th a t it never g ave perfect results, bu t th a t even a trained man could not guaran tee th a t his application would be any im provem en t over none at all. T h is statem ent is based on th e actual perform ances of the testing squad not once b u t m an y tim es in th e course of more than three m onths. T h e failures occurred w ith every in d ivid u al of th e squad. A n im provem ent in the wording of th e directions was suggested, b u t was not put into effect as th e con tract for such of these units as had not been m anufactured was cancelled, because it was evi
dent th a t a m uch better com position would be very soon available.
T h e experim ent was tried of applying the soap dis
solved in vo latile solvents so th a t no rubbing would be necessary. T h is idea also was a com mon thought both in th e U nit and outside of it. W hile there is some doubt as to the d esirab ility of th is method of application, th e failure to prevent dim m ing in the tests was u nd ou b ted ly larg ely due to the fa ct th at the anti-dim m ing com position had to be used on celluloid lenses, as a large proportion of th e gas m asks at this tim e necessarily had such lenses and the prevention of dim m ing on celluloid was m uch more difficult than on glass. E ve n in th e sum m er of 1918, m onths after this question had been left behind, a n y routine te st
ing of m aterial suggested for th e prevention of dimming was m ade w ith celluloid lenses to a vail ourselves of the experience already gained, and because the test was more severe, and g av e more definite results. All our w ork had shown th a t 'if a m aterial prevented dim ming on a celluloid lens it w ould do so on glass. This made it unnecessary to m ake all the tests w ith both m aterials, b u t m an y tests were made using glass lenses.
W hether th e later ty p e of soaps dissolved in a volatile solven t w ould h ave successfully prevented dimming was not; tried, as on repeated application the solvent etched th e surface of the celluloid.
A n oth er idea which failed to give the expected favo r
able results was th a t glycerin in large am ounts would be beneficial. Alone it did not p revent dim m ing, and a soap containing about 25 per cent was not good. I t was recognized th a t some glycerin was de
sirable.
T h e use of soap-im pregnated paper rings to be used as washers and clam ped into th e eye cup w ith the lens was not successful.
T h e earlier com positions tested included:
A nti-dimming paste, the m aterial m anufactured for the Arm y.
“ F o g K iller,” a commercial preparation for keeping an auto
mobile windshield clear from rain drops, which was early suggested for use in the gas mask.
Several special commercial soaps, to see w hether som ething already on the m arket would be efficient.
Experim ental preparations made b y Colgate and Com pany to investigate the effect of solubility o f the soap on its efficiency in the prevention of dimming, potassium oleate as well as acid soaps, and soaps containing added glycerin.
T h e composition made b y leaving out the chalk in the anti- dimming paste w as also tried.
In th e W ashington lab orato ry soaps were m ade from cottonseed and coconut oils w ith soda and w ith sodium and potassium h ydroxides m ixed, neutral soaps, those w ith excess of alkali and those containing added glycerin. A ll these com positions were un
satisfactory. T h e y were not all of the sam e grade, b u t none was sufficiently desirable to su b stitu te for the one already in use.
T h e suggestion had been m ade th a t th e failure of anti-dim m ing com positions was due to carbonic acid in th e m ask atm osphere settin g free the fa tty acid and so m aking th e com position useless, and th a t th e use of the soap of a strong acid, T u rk e y red oil soap for instance, w ould solve the problem . It is not possi
ble to accept this explanation of the failure of these com positions, b u t the m aterial suggested proved to be the best so far obtained.
In cooperation w ith the Am erican U n iversity and the G as Defense Service sam ples were m ade according to th e follow ing directions b y C olgate and C om p an y, A. K lip stein and C om pan y, and the Southern C otton Oil C om pan y:
T o 100 cc. of 50 per cent T u rk ey red oil add 10 g. of d ry sodium carbonate, stir in well and heat on w ater bath until it forms a hard mass on cooling.
These directions are for the product called N o. 7, and the other, called N o. 9, is the same except th at 3 cc. of thick paraffin oil (as used m edicinally) are added.
A t th e tim e it was supposed th a t th e Southern C otton Oil C om p an y used sulfonated cottonseed oil, hence the designation in the d ata given later, b u t it was subsequently learned th a t th e y had purchased and used sulfonated castor oil as th e y did not m anu
factu re sulfonated oils. A. K lip stein and C om p an y prepared sam ples from both sulfonated castor oil and sulfonated corn oil. T h e W ashington lab orato ry also used both these oils. T h e products obtained from th e different sources using identical directions varied from tw o per cent to 30 per cent m oisture, and from a thin paste to a hard mass.
W hen m aterials tested were all poor the result of th e test was m erely the rejection of the com position, b u t these preparations all proved to be m uch more satis
fa cto ry and it becam e necessary to differentiate betw een such preparations. In order to accom plish this, the results of each test were reported in w riting, including q u an titative m easurem ent of vision for each eye at different tim es during the test and the general description of each lens, how much it was fogged, how b adly, etc. T hese reports were exam ined b y one man-, who g ave th e result for each lens a letter grade which applied to the anti-dim m ing com position used. T h e grade “ failu re” m eant th a t a t some tim e during the test, lasting alw ays a t least an hour, the eyepiece was b ad ly dim m ed over tw o-thirds of its area. “ E xcellen t”
•i'ibS T H E J O U R N A L O F I N D U S T R I A L ' A N D E N G I N E E R I N G C H E M I S T R Y Vol. n , No. 12 meant' th a t ’th e vision through the lens was not harm ed
at all as shown b y the reading ch art tests. N um erical values, were assigned to the grades, and the average value fo r each preparation was calculated and called its index num ber. T h e follow ing tab le shows the in
dex num bers obtained in some of the prelim inary work.
A ll sam ples labeled “ W ” were prepared at th e A m er
ican. U n iversity b y T . H. W oodside.
'Ç a b l e I I — I n d e x N u m b e r s o p A n ti- D im m in o C o m p o s it io n s
N o . o p N o . op In d e x
: Ma t e r ia l , ! * Te st s Fa il u r e s N o . Co n siste n c y
C o tto n 9 . , . . , . , . .. . 5 - 0 9 .6 H a rd
C o tto n 7 . . . 7 0 9 .4 H a rd
E-7... . . . 14 , 1 ■ 9 .0 V e ry h a rd
C o rn 7 ... 0 8 .7 S o ft
1 -8 . . ... . . . 18 1 8 .7 T h in p a ste
C o rn 9 ... . . . 19 1 8 . 2 S o ft
■Castor 7 . . . . 21 2 8 . 1 S o ft
1 -7 ... . . . 2 0 1 8 . 1 T h in p a ste
E - 9 ... . . . 11 2 ■ ? . 3 V ery h a rd
• " P a s te ” ... . . . 38 12 5 .5 T h in p a ste
W - 4 . .... . . 1 0 0 9 .6 R a t h e r h a rd
•W- 6 ... . . . 1 1 0 8 .4 R a t h e r h a rd
W - 5 ; . . ... . . . 38 0 8 . 6 H a rd
N o t e —E -7 c o n ta in e d 4 p e r c e n t m o is tu re ; C o rn 9, 33.5 p e r c e n t m o is
tu re ; a n d E -9 o n ly 2.3 p e r c e n t w a te r. T h e se a re all, sav e “ P a s te ,” T u r k e y re d oil p re p a ra tio n .
T hese results showed th a t com positions m ade from the sulfonated oils were far b etter th an the m aterial being furnished the A rm y, and it was necessary to ob
tain know ledge for the spécifications for th e new com positions.
E F F E C T O F V A R I A T IO N I N C O M P O S IT I O N
T h e effect of variation of the am ount of alkali was in vestigated and th e: follow ing data were obtained.
T a b l i î I I I
S a m p l e , .. N a O I I N o o f No. o f I n d e x
N o . G . T e s t s F a i l u r e s No.
•W -3 8 ..ÎV ___ . . . 0 10 1 7 .2
W -3 9 ... S 8 1 7 .3
W -4 0 ... 10 10 0 9 .0
■ W -4.1_______ .’ . . . 15 10 0 8 .0
W -4 2 ... 20 12 0 9 .7
W - 4 3 . ; . . ... 30 10 0 8 . 8
In eyery case th e.soap was m ade from 100 g. of 85 per cen t T u rk e y red oil bought on the open m arket and 5 g. of w ater glass (sirup) plus the am ount of caustic so d a given, in. the tab le. T h e m ixture was warm ed
on the w ater bath to evap orate the excess w ater.
T hese (results indicated th a t a t least ten p arts of .caustic soda should be u sed and th a t tw e n ty were b etter. Since the com position was to be used on celluloid it seemed better to avoid a large excess of alkali, although',such a soap m ade w ith fifteen parts of sodium hydroxide did not visib ly etch celluloid in three d a y s ’ exposure to air, even when m oistened occasionally.
I t was te n ta tiv e ly decided to use ten p arts of caustic soda but th is was increased to fifteen parts, on th e basis of th e follow ing d ata and also of m achine tests in which, the com position containing only ten parts of soda g ave unreliable results. T h e d ata for W-38 and W -39 are repeated for com parison.
Ta b l e I V — Sh o w in g Un r e l i a b i l i t y o f Co m p o s i t i o n s w iT n In s u f f i c i e n t 1 Ex c e s s o f Al k a l i
P a r t s N ajCO »
S a m p l e p e r 100 N o . o f No. o f I n d e x No. P a r t s O i l T e s t s . F a i l u r e s No.
W- 6 ... 19 11 0 8 . 4
W - U ... 9 29 2 8 .3
W- 8 ... .. 9 22 4 6 . 0
W - 3 . . ... 9 15 4 5 .9
W -9 ... 9 23 11 3 . 6
Pa r t so f Ca u s t ic So d a
W -5 ... 5 38 0 8 . 6
W -1 3 ... 7 .5 20 0 8 .9
W - 3 8 ... 0 10 1 7 .2
W -3 9 ... 5 8 1 7 .3
T h e results should be tak en to in d icate not th a t the use of sodium carbonate is undesirable, b u t th a t if no excess of alkali is present th e com position is un
reliable. T h e oil used had an apparen t saponifica
tion value, i. e., including th e free acid present, of 67 mg. caustic soda (89 mg. anhydrous sodium ca r
bonate) per gram.
T h e fa ct th a t W -5 proved to be an excellent anti- dim m ing com position indicates th at the excess of al
kali is n ot the only reason for the excellence of these soaps, bu t th a t the nature of the oil is a factor. Sam ples of neutralized T u rk e y red oil, called alizarine oil, subm itted b y A . K lip stein and C om p an y, g ave less sa tisfa cto ry results, but no index num ber was ca lcu lated . Sulfonated corn oil was used in the prepara
tion of W -9 instead of sulfonated castor oil, bu t the poor q u a lity of the product was not a ttrib u ted to the corn oil bu t rather to th e low alkali content, for this oil required alkali more th an did th e sulfonated castor oil. T h e apparent saponification valu e for the corn oil was 105 mg. anhydrous sodium carbon ate per gram . E v id e n tly in this p reparation th e oil was not com pletely saponified.
T o determ ine w hether the use of w ater glass was beneficial, the follow ing series of sam ples were tested.
A ll th e sam ples were m ade from 100 p arts of 85 per cent sulfonated castor oil and 15 p arts of cau stic soda..
I t was decided to use five p arts of w ater glass.
Ta b l e V — Ef f e c t o f Wa t e r Gl a s s Wa t e r Gl a s s
Sa m p l e Sy r u p No. o f No. o f In d e x
N o . C c. T e s t s F a i l u r e s N o .
W -3 0 ... 0 10 0 9 . 2
W -3 1 ... 2 8 0 9 .8
W -3 2 ... 5 12 0 9 .5
W -3 3 ... 10 12 0 9 .7
A n oth er series of sam ples was m ade to te st th e d e
sirab ility of th e use of paraffin oil, “ N u jo l” was used.
These were all m ade from 100 p arts of the 85 per cent oil, 15 parts caustic soda, and 5 p arts w ater glass.
T a b l e V I— E f f e c t o f N u j o l
Sa m p l e Pa r t s No. o f N o . OF In d e x
N o . Nu j o l Te s t s Fa i l u r e s No.
W -3 4 ... 0 14 0 8 .4
W -3 5 ... 2 8 0 8 .0
W -3 6 ... 5 10 0 9 .2
W -3 7 ... 10 8 0 9 .8
T hese d ata in d icated th a t th e use of paraffin oil was desirable. T h is w as, perhaps, due to th e fa ct th a t celluloid surfaces were being used.
D u p lication of p reparation was im portan t. T h e follow ing sam ples were tested , the d ata for m ost of w hich h ave been given, b u t th e y are repeated in T a b le V I I to in d icate the rep rod u cib ility of such preparations.
T hese sam ples were all m ade using 100 p arts T u rk e y red oil, 15 p arts N aO H , 5 p arts w ater glass, and no N ujol.
T a b l e V I I — R e p r o d u c i b i l i t y o p G o o d M a t e r i a l S a m p l e W a t e r No. o f No. o f I n d e x
N o . P e r c e n t T e s t s F a i l u r e s N o .
W -3 2 ... 2 2 .8 12 0 9 .5
W -3 4 ... 2 1 .8 14 0 8 .4
W -4 1 ... 1 .7 10 0 8 .0
W -4 4 ... 0 .7 10 0 8 . 8
T h e index num ber obtained for sam ple W -41 is low. I t will be noted th a t this sam ple fits p o orly into T a b le II, also. T h e reason for th is rath er low value is not know n. T h e variation shown b y th e index num bers in T a b le V I I was rath er greater th an w a s
