The Journal of Industrial and Engineering Chemistry, Vol. 4, No. 1

T h e E l e c t r i c F u r n a c e L

in th e iV lo d ern L a b o r a to r y

T h e W o r k of a P i o n e e r and What It Brings to You.

T he practical Electric Resistance Furnace of to-day was m ade possible b y the work of one man.

A lb ert L. Marsh recognized the fundamental advantages in electric heat and realized some of the enormous possibilities which it offered.

N i c k e l - C h r o m i u m

was produced b y him after four years' research. T his high m elting-point alloy is now known as the standard resistance elem ent— is the foundation for the lab orato ry E lectric Resistance Furnace.

T h e Q u a lit ie s of E s s e n t ia l S u p e r i o r i t y

in Nickel-Chrom ium are high m elting-poin', high specific resistance and great resistance to oxidation. U pon this heating elem ent as a foundation was built the first “ H oskins” Electric Furnace. Then cam e the H oskins “ h e a v y -d u ty ” Furnace.

Q u ic k . E c o n o m ic a l R c n e w a b ilit y a n d th e a b ilit y to g iv e continuous service, a re th e d is tin c tiv e leatures nf th is F u rn a ce. T o g a in th ese, H r . M arsh in tro d u c e d h e a lin g u n its removable by ike operator and in large cross section.

In 1 9 0 3 one o f th e first o f th ese “ re n ew a b le u n it” E le c tric F u rn a c e s w as in sta lle d in a threat oe n a n t la b o ra to ry . N >w, th e " H j s k i n s ” E le c tr ic F u r n a c e is c a lle d in ­ dispensable in m e ta llu rg ic a l and c h e m ic a l la b o ra to rie s from c o a st to coast.

In Y o u r L a b o r a t o r y , y o u can ob tain th e results th a t a lo n e h a v e b ro u g h t th is abou t. T h e m eans is the H oskin s “ T y p e F B " Electric Furnace, d e s ig n e d b y A lb e r t L . M arsh and e q u ip p ed w ith renewable N ic k e l-C h r o m iu m u n its.

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T IN : M u r ia te of T in C r y sta ls a n d M u ria te of T in S o lu ­ t io n , B ic h lo r id e a n d O x y M u ria te of T in

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NEW ALLOY STEEL STANDARDS

T h e use of a llo y s in steel m akin g is b ecom in g m ore e x ten sive each y ear, e sp e cia lly chrom e, v an ad iu m , and n ickel, a n d m a n y chem ists are now bein g called upon to d eterm in e these elem en ts, w hose exp erien ce in a llo y steel w o rk h as been lim ited . Chem ists doing this k in d of w o rk h a v e been w o rk in g in d e p en d en tly accord in g to d iffe re n t m ethods, and h a v e often w an ted stan d ard s w h ich th e y co u ld rely upon a s b ein g p o s itiv e ly co rrect. T o m eet this re.

qu irem en t, w e h a v e p u t on the m a rk et four d iffe re n t a llo y S tan d ard s, w h ich h a v e been ch e ck e d b y seven of th e best k n ow n a llo y steel chem ists in th e P itts b u rg h d istrict.

T h e an alyses check ed v e r y closely, esp ecia lly w hen the sam e m eth od w as u sed ; for e xa m p le, on the C hrom e V a n ad iu m S tan d ard , four d ifferen t chem ists u sin g the m eth od of o x id atio n w ith P o ta ssiu m P e rm a n g a n a te in a su lp h uric a cid solu tion , rep ort Chrom e as follow s:

1.055 % - 1 .0 7 % - 1 -05

% -

1.07%

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T h e J o u r n a l of I n d u s tr ia l a n d Engineering Ghemistry

Published by T H E A M E R I G A N C H E M I C A L S O G I E T Y

V o lu m e IV____________________________J ANUARY, 1912__________________________ No. 1

B O A R D O F E D IT O R S . Editor: M. C. W hitaker.

Associate Editors :

Geo. P. Adam son, E . G. B ailey, H. E. Barnard, C. A . Brow ne, G. E. Barton, W m . B rad y, W m . Cam pbell, F. B.

Carpenter, V irgil Coblentz, Francis I. D upont, W . C. E baugh , W m . C. Geer, W . F. H illebrand, W . D. Horne, K a rl L angenbeck, A . D. Little, C. E. Lucke, P. C. M cllh iney, E . B. M cCready, W m . M cMurtrie, J. M erritt M at­

thews, T . J. Parker, J. D. Pennock, W . D. Richardson, Geo. C. Stone, E rn st Tw itchell, R obert WaM(\WTji.

H. W alker, W . R. W hitney, A. M. W right. '%•'

P u b lish e d m o n th ly . S u b sc rip tio n p rice to n o n -m em b ers of th e A m erican C hem ical S o c ie ty , $6,00 y early . POLITECHNis, F o reig n p o stag e , sev e n ty -fiv e c en ts, C an a d a . C u b a a n d M exico ex ce p te d . \

\ . i f \

E n te re d a t th e Post-O ffice, E a s to n , P a ,, as S econd-class M a tte r.

T A B L E O F C O N T E N T S . Ed i t o r i a l s:

Som e A p p lic a tio n s of W ro u g h t T u n gsten and M olyb -

d en u m ... 2

“ T h e F e llo w W ho D oesn ’t K n o w A n y B e t te r ” ... 4

Or i g i n a l Pa p e r s: D eterio ratio n and S p on taneou s H e a tin g of Coal in S torag e. B y H orace C. P o rter and F. K . O v i t z . . . . 5

T h e D istilla tio n of A lcoh ol. B y A . B . A dam s, Chief C hem ist, In tern a l R even u e B u re a u ... S P u re Linseed Oil. B y E . J. Sh ep p ard ... 14

A rsen ic in G lass. B y S. R . Sch oles... 16

T h e D eterm in ation of Chrom ium and I ts S ep aration F ro m V a n ad iu m in Steels. B y J. R . C a in ... 17

T h e B ism u th ate M ethod for M anganese. B y D. J. D e m o r e s t... >9 S a lt-R is in g B read and Som e Com parisons w ith B read M ade w ith Y e a s t. B y H enry A . K o h m a n ... 20

A R a p id M ethod for the D eterm in ation of S u lp h u r in R o asted B lende. B y C. C. N it c h ie ... 30

J a m a ica C am phor. B y H W . Em erson and E. R. W e id le in ... 33

T h e In d e x of R efractio n of th e M ixed A cid s o f F a t t y O ils. B y W . B. S m ith ... 3<> T h e C hlorin e C o n ten t of M ilk. B y P a u l P o e t s c h k e .. . 38

T em p eratu re Corrections in R a w S u g a r P o larization s. B y W. D . H o r n e ... 41 La b o r a t o r y a n d Pl a n t: A n E le c tr ic L aboratory' F u rn ace. B y R a y m o n d C. B e n n e r... 43

A S till for A b so lu te A lcohol. B y R a lp h H . M c K e e . . 46

A n A u to m a tic P ip e tte. B y T. O. S m it h ... 47

A N ew M eltin g-P oin t A p p aratu s. B y D. S. P r a t t --- 47

Ad d r e s s e s: A d d ress a t th e U n veilin g of th e B u s t of \\ o le o tt G ibbs. B y C h arles E. M u n ro e ... 48

C h e m i c a l In d u stries in Sw eden. B y T h o m as H . N orton 51 F uel E co n o m y in F acto ries. B y C. E. L u e k e ... 58

D eflocculation. B y E d w a rd G. A c h e so n ... 62

T h e C hem ist and the C o tto n Seed O il In d u s try in A m erica. B y D a v id W esson... 64

No t e s a n d Co r r e s p o n d e n c e: C orrection : T h e P rep a ra tio n and P ro p erties of M e­ ta llic C e r i u m ... 65

T h e M ékcr B u r n e r... 66

Im ports and E x p o rts of F arm ers’ M a te r ia ls... 66

W lia t O ur R iv ers C a r r y ... 67

C em en t P rod u ctio n to 19 1 0 ... 67

W orld ’s P rod uctio n of C o a l... 67

T h e M ineral P ro d u ctio n in N o rth C arolin a d u rin g 1 9 0 8 -1 0 ... 68

C hief G eologist, G eo logical S u r v e y ... 68

N a tio n ’s Coal P r o d u c tio n ... 68

C u b a Iron-O re P r o d u c t io n ... 68

G re a te s t Iro n -P ro d u cin g R egion in the W o r ld ... 68

Illinois Coal P r o d u c tio n ... 68

Coal E x p o rts in 1 9 1 0 ...( ... 68

O il in A l a s k a ... 69

P u re F ood and D ru g L a w in M o n ta n a ... 69

B ureau of M ines A p p ro p ria tio n s... 69

C iv il S ervice E x a m in a t io n ... 69

Bo o k Re v ie w s : H and book ten D ienste van de S u ik erriet-C u ltu r en de R eitsu ik erfab ricag e op J a v a ; T h e M an u factu re of S u lp h u ric A cid and A lk a li ; Die M etallu rg ie des W o lf­ ram s m it besonderer B e r ü c k s ic h t ig u n g d er E le k t r o ­ m eta llu rg ie; A n nu al T a b les o f C on stan ts a n d N u ­ m erical D a ta (Chem ical, P h y sic a l and T ech n o logical) 69 Ne w Pu b l i c a t i o n s... 70

Re c e n t In v e n t i o n s... 72

M a r k e t R e p o r t ... 74

2 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 . Jan.. 1912

EDITORIALS

SOM E A P P L IC A T IO N S O F W R O U G H T TU N G STEN AND M O L Y B D E N U M .

O nly a few years ago a num ber of the elem ents were classed in the literature as b rittle and had never been produced in a condition in which th e y were not brittle a t room tem perature, b u t have since been taken out of the b rittle list. A m ong these are tungsten and m olybdenum .

P rior to their production in ductile form, tungsten and m olybdenum as such (th at is, other than in alloys or com pounds) had b u t one application, nam ely, in an incandescent lam p, the one as filam ent, and the other as filam ent support.

Some of the p h ysical properties of these last-nam ed industrially new elements, together w ith a rough sketch of the investigation w ork leading up to the pro­

duction of ductile tungsten, h ave been published elsewhere {Trans. Am . Electrochem. Soc., 17, 229-234 (1910 ); Proc. A m . Inst. E . E ., 29, P a rt II, 961-965 (1910)).

It is the purpose of this paper to tell of som e of the applications which are being developed for w rought tungsten and w rough t m olybdenum . T h e w riter presents it not o n ly for the interest of the w ork itself, bu t also in the hope th a t it w ill stim ulate w ork on the other so-called b rittle m etals, and it seems to him th a t some of our industries are alm ost certain to profit g re a tly b y the discovery of each new ductile elem ent.

T H E D R A W N - W I R E T U N G S T E N IN C A N D E S C E N T L A k lP .

A yea r and a half ago the hope w as first p u b licly expressed th a t it w ould soon be possible to m anu­

factu re lam ps on a large scale from ductile tungsten.

T his hope has been fulfilled, and the com m ercial de­

velopm ent has been so rapid th a t already the b ulk of the tungsten lam ps m ade in this co u n try are of drawn wire, and the m an ufacture is alread y estab ­ lished on a - large scale in E n glan d and G erm any.

Som e a n x ie ty was a t first felt lest it should not be possible to g et diam ond w ire draw ing dies of suffi­

cien tly sm all aperture to produce wire fine enough for the .lowest candle pow er lam ps w hich m ight be desired. B u t this fear proved groundless and w ire is now produced in q u a n tity down to 0.0006 inch in diam eter.

D uctile m olybdenum is used in some typ es of lam p as a support m aterial for the tungsten filam ent.

T H E T U N G S T E N O R M O L Y B D E N U M -W O U N D F U R N A C E .

T his has already been described b y W inne and D antsizen ( Th i s Jo u r n a l, i g u , p. 770), and has proved to be an exceedin gly useful tool, especially so in con­

nection w ith the production of w rough t tungsten and m olybdenum . E x te n siv e fa cto ry use has shown it to be not only cheaper but, regardless of cost, far superior to a platinum -w ound electric furnace. W hen w ound on a b o d y of alundum it perm its of the a tta in ­ m ent of higher tem perature than can be reached w ith platinum . This attain m en t of the higher tem pera­

ture is often in itself an advan tage, and it is alw ays an advan tage, in industrial w ork, to be relieved from the necessity of using the strictest tem perature con­

trol to avo id m elting a furnace winding. T h is is especially tru e in cases where the tim e consum ed in heating up th e w ork in the furnace is im portant.

F or in these cases m uch tim e is saved b y not using a constan t current su p p ly to the furnace winding, b u t b y first raising the current, upon the introduction of the cold w ork, and then bringing it dow n as the tem perature of th e w ork rises.

E L E C T R IC A L C O N T A C T S O F T U N G S T E N A N D M O L Y B D E N U M .

T ungsten and m olybdenum are destined to p la y a ve ry im portan t role in the field of contact-m akin g devices. This is due to their high m elting point, which prevents them from w elding togeth er; to their h eat co n d u ctiv ity (about tw ice th a t of platinum ) w hich tends to keep down local tem perature rise; and to their hardness, w hich enables them to stand re­

peated im p act w ith ou t flatten in g out.

T h e n atu ral assum ption w ould be th a t both m etals under the h eat of even m inute arcs, w hich form when th e contacts are separated, w ould oxidize a t the points where arcin g has tak en place and th a t non­

conducting layers w ould thus be form ed w hich w ould produce a high and variab le co n tact resistance. B u t several things interven e to p reven t this. First, there is the re la tiv e ly good h eat co n d u ctiv ity of the dense form of these m etals, w hich distributes the heat.

Then the fa ct th a t the m etals are m uch less expensive than platinum , fo r exam ple, m akes possible th e use of larger co n tact ■ masses, w hich again m ilitates against strong local heating. F in ally, there is th e fact th a t w ith both tun gsten and m olybdenum the oxides w hich form in the presence of a sufficiently lim ited am ount of oxygen are conducting.

Som e prom ising applications which are being tested ou t are the follow ing:

A s an iridium su b stitu te in the ‘ ‘m aster” contacts of T irrell vo lta g e regulators.

A s a silver su b stitu te in the rela y con tacts of Tirrell vo ltage regulators.

A s an iridium su b stitu te in feed-w ire vo lta g e reg­

ulators.

A s a platinum su b stitu te in railw a y signal relays.

A s a su b stitu te for platinum -iridium in the contacts of a synchronously driven vib ra tin g m echanical rectifier.

A s a platinum su b stitu te in telephone jacks.

A s a platin um su b stitu te in autom obile and sta ­ tio n ary gas-engine ignition w ork, for spark coil con­

tacts, m agneto circuit-breaker contacts, and spark plugs.

In connection w ith the ab o ve there w as a t first serious difficulty in g ettin g sa tisfa cto ry heat contact betw een tun gsten or m olybdenum on th e one hand, and iron or b ra ss,'a s the case m ight be, on the other.

Jan., 1 9i2 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 . 3 T h is was due to the fa ct th at neither tungsten nor

m olybdenum can be satisfactorily soldered b y any of the ordinary processes. This difficulty has been finally entirely overcome.

T U N G S T E N A S T A R G E T IN A R Ö N T G E N ( X - R A Y ) T U B E .

T his has proved to be, both from the scientific and practical points of view , an excep tionally inter­

esting application.

U n til recently platinum has been alm ost universally regarded as the best target m aterial, and it has so long held undisputed sw ay in this field th at the R öntgen r a y w orker has come to look upon its lim itations as inherent in the R öntgen tube.

I t has not been possible until recen tly to produce dense, forged pieces of pure m alleable tungsten. B u t w ith the adven t of this m aterial, the possibilities of the R öntgen tube are greatly extended.

T he desiderata in a m aterial to be used as the an ti­

cathode or target are the following:

1. High specific g ra vity.

2. High m elting point.

3. High heat conductivity.

4. Low vap o r pressure a t high tem perature.

T h e reasons w h y the above qualities are desirable follow readily from a brief consideration of the th eory of R öntgen-ray production.

From the concave cathode, electrically charged particles, the electrons, are shot out a t high v e lo city in a direction norm al to the surface. T h e paths of these particles converge and the target is placed a t or near the point of strongest convergence, the focus point. W hen the electron m eets an obstruction, as the target, its ve lo city is reduced, and the denser the target the more rapid is the deceleration. T h e more rapid the deceleration the greater is the am plitude of the electrom agnetic pulse, the R öntgen-ray, sent out.

Here then is a need for high specific g ra v ity ; th at of forged tungsten is b u t little less than th at of platinum .

In m odem R öntgen-ray practice, powerful apparatus running sometimes to a cap acity of six kilow atts is used to excite the tube. T he greater p a rt of the energy delivered to the tube is transform ed into heat a t the point w here the cathode rays bom bard the target.

W here platinum is used it has been found necessary, to prevent m elting, to place the target beyon d the focus of the cathode so as to spread the bom bardm ent over a larger area. A s a radiograph is a shadow picture, and as the source of the R öntgen-ray is the bom barded area of the target, this enlarging of th at area is clearly an undesirable thin g to do, as the larger area w ill mean more overlapping and less definition in th e resulting picture. In th is w ay, the m elting point of platinum has been the lim iting feature of the R öntgen tube. T h e ca p a city of the tube has been in­

creased b y w ater cooling the platinum or b y using as a target a large mass of copper h avin g a v e ry thin platinum face. B u t the lim it, although raised b y this artifice, has still been the m elting point of the platinum .

Tungsten has a much higher m elting point (30000 C.

as against 1755° for platinum ), and so, even w ith sharp focusing of the cathode rays on the target, per­

mits the iise of more energy th an has hitherto been possible; for the high tem perature to which it can run enables it to radiate more heat, and its b etter heat co n d u ctiv ity perm its a more rapid flow of heat from the focus spot to the surrounding m etal.

S ta b ility of vacuum in a R öntgen tub e is of the utm ost im portance, as the character of the rays is so largely determ ined b y the vacuum . Metal, which under the influence of the high tem perature vaporizes from the target, condenses on the glass in finely divided form and absorbs relatively large am ounts of gas, thus changing the vacuum . A t high tem pera­

tures tungsten vaporizes least of all the m etals.

In the above case, practice seems to be in full accord w ith the theory, and the tungsten target offers great prom ise to the R öntgen-ray worker. I t gives him w hat he has not had before, an indestructible target, so far as the present electrical apparatus goes, together with sharper definition and m uch shorter exposure.

T U N G S T E N P R O J E C T I L E S .

The use of w rought tungsten as a projectile is being carefu lly investigated. I t offers, in this field, possi­

bilities not possessed b y a n y other m etal.

T h e present sm all arm service projectile is m ade of lead w ith a ja c k e t of copper-nickel alloy. T h e prin­

cipal advan tage ■ of lead over iron, w hich w ould of course be cheaper, is th a t it has a higher specific g ra v ity. Because of this fa c t a lead bu llet w ill h ave a sm aller cross-section, and' w ill therefore encounter less air resistance to its flight, than w ill an iron bullet of the sam e w eight, and w ill therefore g iv e a flatter tra je cto ry and longer range. A n iron bu llet of the sam e diam eter as the lead bu llet could of course be given th e sam e w eigh t b y increasing its length. B u t th is w ould a t once necessitate giv in g it a higher rotational v e lo city to keep its axis tan gential to its flight. T o im part this added rotational v e lo city calls for the expenditure of energy and so leaves less for v e lo city of translation. T h e lead bu llet then w ith its higher density m akes possible a flatter tra jecto ry and longer range. W ith the exception of tungsten, lead is the densest m etal w hich can be considered for this purpose, for gold is the cheapest of th e other elem ents h avin g a higher specific g ra v ity than lead.

T h e density of w rough t tungsten is 19.3 w hile th a t of lead is 11.5.

For m ilitary purposes, the softness of lead is not an advan tage, a soft nosed bu llet being tabooed in civilized w arfare. F or this reason and because of the fa ct th a t it is too w eak to hold the rifling, it has to be jack ete d w ith the copper-nickel alloy. T o take the rifling and to act as a gas check, the tungsten bullet w ill require a copper ban d or its equivalent a t the base.

T h e hardness and high tensile strength of w rought tungsten will g ive high pen etratin g power.

T h e high m elting point of tungsten w ill p reven t it from being h arm fu lly upset a t the base b y the com ­ bined action of the high tem perature and rapid im ­ p a ct due to the com bustion of th e pow der charge.

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 . Jan.. 1912 (A n unsym m etrical upsetting of the base of a pro­

jectile is v e ry prejudicial to accuracy.)

I t w ould be a v e ry sim ple m atter to calculate the constants of th e tra je cto ry of a tungsten projectile were it not for the fa ct th a t the high d ensity rem oves it too far from the present base line. F or such calcu­

lations one q u a n tity is lacking, the so-called “ form fa cto r.” T his factor could itself be calculated if it contained, as the ñam e w ould seem to im ply, only the dimensions and the specific g ra v ity ; b u t there are also in volved in it all of the errors d u e . to sim plifying assum ptions w hich h ave been m ade in connection w ith the m athem atical derivation of form ulae. It therefore becom es necessary to exp erim entally deter­

mine the constants of the tra je cto ry of tungsten bullets, and preparations for this w ork are now bein g

m ade. W . D. Co o l i d g e.

“ T H E F E L L O W W H O D O E SN ’T K N O W A N Y B E T T E R .”

There are in the U nited S tates according to the census m ore than eight thousand chem ists. Most of these chem ists h ave spent a t least three years and m any have spent six or seven years in the college or u n iversity acquiring a know ledge of chem istry.

A b o v e all other men th e y are acquainted w ith chem i­

cal law s and processes. A ccordin g to President M aclaurin and President Low ell, to ju d ge from some of th eir co m p aratively recent addresses, the earth and the fulness thereof during the present cen tu ry is to belong to the chem ist. A side from his meekness, how ever, does th e chem ist to d a y show a n y indications of entering into his inheritance? Is the chem ist tod ay, in this country, originating as m an y new products and processes as he should ? Is he even originating his fair proportion of new chem ical products and processes?

In the older and more strictly chem ical industries, such as the acid, h e a v y chem ical, alkali and dyestuff industries for instance, the chem ist seems to be in control and progress in these industries m ay be credited to him. B u t there are other industries in w hich chem ical principles of the highest order are involved which for the m ost p art are n o t under chem ­ ical control; such as, the paint, varnish, dyeing, leather, alloy, shoe ink and shoe polish industries.

There are in some instances chem ists in control who are m akin g good, b u t for the m ost p art the chem ist in such industries as are m entioned above is em ­ p loyed in testing raw m aterials and finished products.

H e m ay be even essentially ignorant of the m anu­

factu rin g processes.

Consider, for exam ple the m an ufacture of shoe inks and polishes. These are im portant industries and the m anufacture of these products is a chem ical process. M oreover, A m erican shoe inks and polishes are sold all over the world, some of our largest com ­ panies h avin g branch factories in E ngland, G er­

m an y and France. B u t in this essentially chem ical industry there are alm ost no chem ists. T h eir prod­

u cts and processes have, for the m ost p art a t a n y rate, originated w ith rule-of-thum b men, the so-called

practical men. Conditions in the other industries m en­

tioned are similar, though in a lesser degree perhaps.

T h e first really successful one-set edge ink for shoes w as stum bled on b y a m an who added a basic color to an em ulsion of ca m au b a w a x and soap, instead of an acid color as called for b y the form ula. If he had been a chem ist he w ould have know n better. He w ould h ave know n th a t a basic color w ould undergo double decom position w ith the soap, causing a coagu ­ lation of the emulsion. T h a t is ju st w h at the basic color did in this case, b u t after stirring and straining it w as ju st as fluid as before. The blackin g m an now throw s his w a x w ith acid to g e t the desired result.

W h at chem ist in his right m ind w ould h ave added acid to an em ulsion of w a x and soap expecting' to ob­

tain a desirable result?

I t keeps the chem ist b u sy stretching his conception of chem ical laws, theories and hypotheses to explain how the despised rule-of-thum b man gets the results he does.

The chem ist, a t a n y rate the common, garden- v a rie ty of chem ist, suffers from a sort of chemico- sclerosis. His conceptions of chem ical law s b e­

com e hardened and his theories and hypotheses inflexible. H e know s th a t sodium chloride added to a silver salt solution produces a precipitate, b u t until colloids becam e fashionable how m an y chem ists knew th a t in the presence of a p rotective colloid-like album en the silver chloride w ould n o t'p r e c ip ita te ? H e know s th a t silver iodide, brom ide and chloride are insoluble and concludes t h a t " silver - fluoride is also. H e know s th a t hydrogen sulphide gives b lack m ercuric sulphide w ith a solution of m ercuric chloride and so the U nited States Pharm acopoeia states th at under the conditions of the ‘ G u tzeit T e s t’ , for arsenic, hydrogen sulphide gives a b la ck stain. U nder usual conditions, how ever, the stain is yellow and m ay be th ou gh t to indicate arsenic.

T h e chem ist finds it difficult to w ork w ith ou t a th eory and neglects to follow the leads th a t according to his th eory do n o t prom ise results. B u t results h ave been obtained th at were not in ex a ct accor­

dance w ith the preconceived theory. P erkin had a th eory for m aking quinine and found the first aniline dye in spite of this theory.

T here is also a certain chem ical snobbery th a t prevents chem ists follow ing leads of dubious respec­

ta b ility . In 1873 it was discovered th a t a dye resulted from the fusion of sawdus^ and sodium sulphide.

T h e d ye w as w eak and of no ascertainable con stitu ­ tion, b u t th a t such a fusion g av e a d ye a t all w as a h igh ly significant fa ct and even a m oderate am ount of investigation w ould h ave im proved this d ye ten ­ fold. B u t as the fath er of the d ye w as saw dust, of course, - no self-respecting chem ist w ould recog­

nize it, and nothing w as done on sulphur colors u ntil tw e n ty years later a sulphur dye of p erfectly respec­

tab le parentage w as discovered. Then hundreds of chem ists were set.to tillin g the field.

T he practical, rule-of-thum b m an w ith a n atu ral ben t for research labors under none of these h andi­

caps. He is free. H e staves ahead untram m eled b y th eory and now and then gets the result. He

Jan., 1912 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 . ₅ m ay p u t on the m arket a wood stain reeking w ith

am m onia as an acid stain bu t it sells and does the work. He gets results often enough to lend a color of tru th to the statem ent th at “ I t ’s generally the fellow who doesn’t know any better who does the thin g th at can ’t be done.

D E T E R IO R A T IO N AND SPO N TA N E O U S H E A T IN G O F C O A L IN S T O R A G E .'

B y Ho r a c e C. Po r t e r a n d F . K . Ov i t z. R eceived D ecem b er 11, 1911.

N ot m any years ago, coal was com m only regarded as an extrem ely unstable m aterial, subject to ve ry serious alteration and losses on exposure to the ele­

ments. E . C. Pechin, in 1872, speaking before the Am erican In stitute of Mining Engineers, says: “ Fuel suffers m aterially b y storage; especially w ith b itum i­

nous and semi-bitum inous coals is the loss heavy, an exposure of on ly two weeks causing a loss of carbon to the exten t of 10 to 2 5 % .” Sim ilar view s have been held in much more recent times. F or exam ple, in a paper before the U. S. N aval In stitu te in 1906 we find the statem ent: “ The pressure of the w eight of coal causes gases to be evolved ; these gases constitute the chief and only value of the coal in th a t th ey furnish the heat units. I t is claim ed th at if a ton of fine bitum inous coal be spread out on a concrete pavem ent in the open air in this clim ate (K e y W est, Florida) for one year, it w ill lose all its calorific properties. The gases are sim ply free to escape, and when the coal has lost all its gas it will h ave lost all its heat units and be sim ply co k e.”

This was only five years ago.

In 1907 a German gas-works engineer claim s to have found that moist fine coal sustained an average loss per w eek of 1.7 per cent., this loss being due to gas.

T he 1889 edition of Groves and T h orp ’s “ Chem ical T ech ­ nology of F u els” says: “ In some places coal is known to lose 50 per cent, of its heating value in six m on ths.”

O ther statem ents like these are to be found in recent literature, b u t probably the great m ajo rity of chem ists and engineers to-d ay hold no such exaggerated ideas on the subject. There is, on the other hand, a well- defined suspicion, in the minds of m any th a t suffi­

cient loss of volatile m atter and sufficient deterio­

ration b y oxidation does occur in coal to be of indus­

trial im portance; and for th a t reason the investi­

gations described in this paper were undertaken b y the Bureau of Mines to determ ine accu rately the exten t of the deterioration in different typ es of coal.

First a stu d y was made in the lab oratory of the loss of volatile m atter from crushed coal during stor­

age. A num ber of samples (20 lbs. each), representing a v a rie ty of types from w idely separated fields, were broken to about I/2-mch size and im m ediately placed

1 P rese n ted , b y perm ission of th e D irecto r, B u re a u of M ines, a t a jo in t m e e tin g of th e N ew Y o rk Section, A m erican C hem ical S o ciety , A m e ri­

c a n E lectro ch em ical S o ciety , a n d th e S o ciety of C hem ical In d u s tr y , N ew Y o rk . N o v em b er 10, 1911.

The fellow who doesn’t know any b e tte r ,” will not m ake this cen tury the cen tury of chem istry. It will be done b y the chem ist who realizes the flexi­

b ility of our great laws, the in stab ility of hypothesis, the u nreliability of analogy and who is not afraid of the dark. W . H. W a t k i n s.

in glass bottles in the mine. A t the lab oratory the accum ulated gas was w ithdraw n and a free con­

tinuous escape of the volatile products perm itted a t atm ospheric pressure and tem perature. The results of these experim ents have been published in T ech ­ nical P aper No. 2, B ureau of Mines, entitled “ The E scape of Gas from C o a l” and w ill therefore not be given here in detail. Suffice it to sa y th at while several coals evolve m ethane in large volum es es­

p ecially in the early period after m ining the coal suffered in one year a loss in calorific valu e from this cause of b u t 0.16 per cent., as a m axim um .

It seems therefore th a t the loss due to escape of volatile m atter from coal has been g re a tly overesti­

mated.

A t the instance of the N a v y D epartm ent, however, which is a purchaser of coal to the exten t of tw o or three million dollars annually, and stores large lots in w arm clim ates for long periods of tim e, more elab­

orate tests were undertaken to determ ine the total loss possible in high-grade coal b y w eathering. The exten t of the saving to be accom plished b y w ater subm ergence as com pared to open-air storage w as a point to be settled, and there had also arisen the question as to w hether salt w ater possessed a n y pe­

culiar advan tage over fresh w ater for this purpose.

A n English railw ay and dock superintendent in an article in the London Engineer, 1903, reports th at he has found coal accidentally subm erged for 10 years in th e salt mud of the E nglish Channel, a ctu a lly im proved in calorific value b y 1.8 per cent, w hich offers a v e ry p re tty question to chem ists to say w h y .” He claim s th a t salt will preserve the v ir ­ tues of coal as it does those of m any other things,

“ if coal is given a strong dose of coarse salt and w ater 12 hours before using, its calorific value is greatly im proved. ”

Coal-storage problem s h ave assum ed im portance during the last few years on accoun t of the uncertain­

ties of supply due to strikes and transportation diffi­

culties. T h e n aval coaling stations, the Panam a R. R . Co., the G reat Lakes com m ercial coal dis­

tribu ting companies, large coke and gas or power plan ts a t a distance from the coal fields and the rail­

roads them selves, p articu larly those in the west, keep 50,000-500-000 tons in storage a great deal of the time.

In brief outline, the tests b y the B ureau were carried out as follows: four kinds of coal were chosen:

N ew R iv er on accoun t of its large use b y the N a v y ; Pocahontas as a w id ely used steam ing and coking

ORIGINAL PAPERS.

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 . Jan., 1912 coal in the eastern section, and as being also the prin­

cipal fuel used in the Pan am a canal w ork; P itts ­ burgh coal as a typ e of rich coking and gas coal; and Sheridan, W yom ing, subbitum inous or “ b la ck lig­

n it e ” — a ty p e much used in the west. W ith the N ew R iv e r coal, 50-pound portions w ere m ade up out of one large lot, w hich had been crushed to 1/i- inch size and w ell m ixed. These portions confined in perforated wooden boxes were subm erged under sea w ater at three n a v y yards, differing w id ely from each other in clim atic conditions, and 300-pound portions from the sam e original lot w ere exposed to the open air, both out of doors and indoors, a t the sam e places.

W ith the Pocahontas coal test was m ade only a t one point, the Isthm us of P an am a— run-of-mine coal being placed in a 120-ton pile, exposed to the w eather. P ittsb urgh coal w as stored as run-of-mine in open outdoor bins, 5 tons cap acity, a t Ann A rbor, M ichigan, also in 300-pound barrels subm erged under fresh w ater. T h e W yom in g subbitum inous was stored a t Sheridan, both as run-of-m ine and slack in outdoor bins, holding three to six tons each.

E v e ry test portion w as sam pled each tim e in dupli­

cate and in all cases excep t the outdoor pile a t P anam a and the 300-pound open-air piles of N ew R iver coal the sam pling was done' b y rehandling the entire am ount. In the excep ted cases m entioned it w as not th ou gh t fair to disturb the entire lot, and therefore a t Pan am a a vertical section of ten tons on ly was rem oved each tim e (eight sam ples being taken from the io-ton section), w hile in the case of the outdoor lots at the N a v y Y a rd s a num ber of sm all portions, w ell-distributed, w ere taken from each pile, m ixed, and quartered down.

Sm all lots and a fine state of. division were con­

ditions purposely adopted w ith the N ew R iv e r coal so as to m ake the tests of m axim um severity.

Moisture, ash, sulphur, and calorific valu e deter­

m inations were m ade on each sam ple, th e la tte r b y means of the M ahler bom b calorim eter and a care­

fu lly calib rated B eckm ann therm om eter. T h e calori- m etric w ork on all excep t the Sheridan, W yom ing, tests has been done throughout b y one man, Mr.

O vitz, and w ith the same instrum ent. A ll the calo­

rific values in the tables h ave been calculated to a com ­ parable u nit basis, viz., th a t of the actual coal sub­

stance free of m oisture, sulphur, and corrected ash.

T h e results show in the case of the N ew R iv e r coal less th an 1 per cent, loss of calorific value in one year b y w eathering in the open. There was p ractically no loss a t all in the subm erged sam ples and fresh w ater seem ed to “ preserve the v ir tu e s ” of th e coal as w ell as salt. There w as alm ost no slacking of lump in the run-of-m ine sam ples and th e crushed coal in all cases deteriorated more rap id ly than run-of- mine.

T he Pocahontas run-of-m ine in a 120-ton pile on the Isthm us of P anam a lost during one y e a r's outdoor w eathering less than 0.4 per cent, in heating value,

and suffered little or no physical deterioration of lumps.

T h e P ittsb urgh gas coal during six m onths’ outdoor exposure suffered no loss w h atever of calorific value, m easurable b y the calorim etric m ethod used, not even in th e upper surface lay e r of the bins.

The W yom in g coal lost as m uch as 5.3 per cent, in one of the bins during tw o and three quarter years, and 3.5 per cent, even in the first three m onths. There was b ad slacking and crum bling of the lum ps on the surface of the piles b u t w here the surface w as fu lly exposed to the w eath er this slacking did not p en etrate more than 12-18 inches in the 23/t-year period.

No outdoor w eathering tests h ave been m ade b y the B ureau on coal of the Illinois type. Thorough tests, how ever, on this typ e have been reported b y Prof. S. W . Parr, of the U n iversity of Illinois, and b y A . Bem ent, of Chicago, both of whom find from 1.0-3.0 per cent, in calorific loss in a yea r b y w eathering. Mr. B ennet reports a slacking of lum ps (in tests on sm all sam ples) of over 80 per cent, in one case and about 12 per cent, in another. It is probable th a t in this ty p e as in the W yom ing, the slacking in a large pile w ould not pen etrate fa r from the surface.

Storage under w ater u nquestionably preserves the heating valu e and th e ph ysical strength of coal. B u t it p ractically necessitates firing w et coal, and there­

fore m eans the evap orating in the furnace of an am ount of m oisture va ryin g from 1 -1 5 per cent., according to the kind of coal. This fa cto r is an im­

p o rtan t draw back to under-w ater storage w ith coals like the Illinois and W yom ing types, w hich m echan­

ica lly retain 5 -15 per cent, of w ater after draining, b u t in case of the high-grade eastern coals, if firemen are perm itted, as is ordinarily th e case, to w e t down their coal before firing, “ so as to m ak e,” as th ey say, “ a h otter fire,” then th e addition during storage of the 2 or 3 per cent, m oisture w hich these coals retain w ould be of little consequence. Subm ergence storage is an absolute p reven tative of spontaneous com bustion, and on th a t account alone its use m ay be justified w ith some coals, b u t m erely for the sake of the savin g to be secured b y avoidance of w eathering there does n o t seem to be good ground for its use.

S P O N T A N E O U S C O M B U S T IO N .

Losses in coal due to spontaneous heating are a m uch m ore serious m atter. O xidation, i. e., p rob a­

b ly in th e m ain an absorption of oxygen b y the un­

satu rated chem ical com pounds in the coal substance, begins a t ordinary tem perature in a n y coal, a ttack in g th e surfaces of the particles, thus slow ly developing heat. In a sm all mass of coal this slow ly developed heat can read ily dissipate itself b y radiation and no rise in tem perature results. If radiation is restricted, how ever, as in a large pile densely packed, the tem ­ perature slow ly rises. Now, the cu rve of oxidation rate p lotted against tem perature rises w ith great rap id ity, and when the storage conditions are such as to allow a certain point (near 1000 C.) to be passed the rate of oxidation is great enough ordinarily so

Jan., 1912 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 . 7 th at the heat developed overbalances the heat radi­

ated and the tem perature w ill rise to the ignition point if the air supply is adequate. The im portance therefore can be seen of guarding against even moderate heating in the coal either from internal spontaneous causes or b y radiation from external sources. In­

creased loss of heating value and of volatile m atter occurs a t m oderately increased tem peratures even though the ignition point is not reached.

T he am ount of surface exposed to oxidation in a given mass depends on the size of the particles and increases ve ry rapidly as the fineness approaches th at of dust. D ust is therefore a dangerous thing in a coal pile, particularly if it is m ixed w ith larger sized coal which forms air passages to the interior. Spon­

taneous com bustion is brought about b y slow o x i­

dation in an air supply sufficient to support the o x i­

dation b u t insufficient to carry aw ay all the heat formed. There is a wide variation am ong coals in friab ility. In com parative rattler tests under cer­

tain standard conditions, Pocahontas. New R iver and Cam bria Co., Pa., coals produced nearly tw ice as much dust (through ■/," screen) as a sam ple from the P ittsburgh seam. This is a large factor in spon­

taneous combustion. M ixed lum p and fine, i. e..

run-of-mine, w ith a large percentage of dust, and piled so as to adm it to the interior a lim ited supply of air, m ake 'ideal conditions for spontaneous heating.

High volatile m atter does not of itself increase the lia b ility ' to spontaneous heating. A recent cir­

cular letter of inquiry on spontaneous com bustion sent b y the Bureau to more than 2,000 large coal con­

sumers of the U nited States has brought 1,200 replies, of which 260 report instances of spontaneous com ­ bustion, 220 of them, nam ing the coal. O f these 220, 95 are in semi-bituminous low -volatile coals of the A ppalachian region, and 55 in western and middle western coals. This result shows a t least no falling behind on the part of the “ sm okeless” ty p e and no cause for placing special confidence in these coals for safe ty in storage.

A serious fire in cinder filling under a m anu­

facturing plant in P ittsburgh was recently investi­

gated b y the Bureau and all the evidence pointed to spontaneous com bustion as the cause, induced b y external, heat radiated from a furnace. T he cinders contained 40 per cent, of carbon. A sim ilar fire occurred tw o years ago in cinder filling under a sm elting plan t on Staten Island in w hich case the cinders contained 33 per cent, carbon. D am age am ounting to $20,000 was done. The cause was not definitely determined, b u t from the reports of the insurance adjusters spontaneous heating appears to be the m ost plausible explanation The volatile m atter in the m aterial could not have been a factor in these causes.

P ocahontas coal gives a great deal of trouble w ith spontaneous fires in the large storage piles a t Panam a.

I t is reported also b y several large b y-p roduct coke concerns to be more troublesom e in this respect than their high volatile gas coals. T he high volatile coals of the w est are, to be sure, usually ve ry liable to

spontaneous heating, b u t th ey owe this prop erty to chem ical nature of the substances which compose the coal rather than to the am ount of volatile m atter.

Strange as it m ay seem, a high oxygen content in coal appears to parallel its a v id ity for oxygen and to prom ote therefore its tendency to spontaneous com bustion.

The influence of m oisture and th a t of sulphur upon spontaneous heating of coal are m ooted questions much discussed, not v e ry much 'actually investigated, and certain ly not y e t settled. Richters has shown th a t in the laboratory d ry coal oxidizes more rapidly than moist, but the w eight of opinion am ong practical users of coal is th at m oisture prom otes spontaneous heating. The observation b y the B ureau of m any actual cases has not developed any instances where m oisture could be proven to have had such an effect.

Sulphur on the other hand has been shown b y these investigations,- to have in m ost cases only a minor in­

fluence. In a num ber of actual cases, sam ples of the heated coal from areas where the heat was greatest have been analyzed, both for the to ta l sulphur and th at in the sulphate form. The difference betw een these, or in other words, the unoxidized sulphur was in no case less than 75 per cent, of the average total sulphur in the original. In other words, n ot more than '/i of the total sulphur has entered into a n y heat-pro­

ducing reaction. The possibility remains, however, th a t all of the sulphur which was oxidized was con­

cen trated in one pocket of m oist flak y pyrites, and thus sufficient heat was developed in one spot to act as an igniter. On the other hand, a Boston com pany, using Dominion (N ova Scotia) coal of 3-4 per cent, sulphur, has much trouble w ith spontaneous fires in storage, b u t a num ber of samples taken b y the B ureau from exposed piles of this coal in which heating had occurred showed th at 90 per cent, of the sulphur was still unoxidized. Experim ents in the laboratory, passing air over coal a t 120° C., have developed enough heat to ignite the coal and no change w as found in the form of the sulphur. W hile not entirely con­

clusive, these results point to a ve ry minor contribu­

tion, if any, on the p art of sulphur to spontaneous heating in coal.

Freshly mined coal and even fresh surfaces exposed b y crushing lum p coal exh ibit a rem arkable a v id ity for oxygen, b u t after a tim e becom e coated w ith o x i­

dized m aterial, " seasoned” as it were, so th a t the action of the air becom es m uch less vigorous. It is found in .practice th a t if coal, which has been stored for six weeks or tw o m onths and has even becom e already . som ew hat heated, be rehandled and thoroughly cooled b y the air, spontaneous heating rarely begins again. A large pow er p lan t in N ew Y o rk crushes its coal to pass a 4" screen im m ediately a fter unloading from barges, the fines and dust, 50 per cent, or more, being left in the coal to be stored. T his freshly crushed coal is elevated to iron hopper-shaped bunkers directly over the boilers and the air tem perature in these often reaches 100 0 F . A s the coal hangs on the sloping sides som etimes three or four m onths at a time, it seepis h ard ly surprising th a t some of the bunkers are on fire p ractically all of the tim e.

8 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 . Jan., 19x2 W ith full appreciation of the fa ct th a t an y or all

of the follow ing recom m endations m ay under certain conditions be found im practicable, th ey are offered as being advisable precautions for safe ty in storing coal w henever their use does not involve an unreason­

able expense:

(1) D o not pile over 12 feet deep nor so th a t any point in the interior w ill be over 10 feet from an air- cooled surface.

(2) If possible, store only lump.

(3) K eep dust out as much as possible; therefore reduce handling to a minimum.

(4) P ile so th at lum p and fine are distributed as evenly as possible; not as is often done, allow ing lum ps to roll down from a peak and form air passages a t the bottom .

(5) R ehandle and screen after tw o months.

(6) K eep aw a y external sources of heat even though m oderate in degree.

(7) A llow six w e e k s’ “ seasoning” a fter m ining before storing.

(8) A vo id alternate w e ttin g and drying.

(9) A vo id adm ission of air to interior of pile through interstices around foreign objects such as tim bers or irregular brick w ork; also through porous bottom s such as coarse cinders.

(10) Do not try to ve n tila te b y pipes as more harm is often done than good.

T H E D IS T IL L A T IO N O F A L C O H O L .1 B y A . B . Ad a m s, C hief C hem ist, In te r n a l R ev e n u e B u re a u .

R ec e iv e d J u l y 13, 1911.

T h e production of alcohol differs essentially from the production of straigh t w hiskey, because it is necessary th a t the finished product be as near pure eth yl alcohol as is possible, b y m echanical means, to distil. T o effect this the processes are essentially the same up to a given point ; th a t is, as far as the p ri­

m ary distillation, this being conducted in a continuous beer still w hich is b u ilt e x a c tly sim ilar to the continu­

ous beer still used in a m ajo rity of the “ B ou rb on ” houses. The distillate, how ever, is produced a t a m uch higher proof, gen erally a t ab out 160 degrees or 80 per cent, alcohol b y volum e. The high wine distillate is reduced w ith w a ter to ab o u t 101 proof, and passed through charcoal filters under pressure. A fte r filtering, the spirit is em ptied into the k ettle of the “ colum n”

still. This still consists of a se rie s of plates ranging in num ber from 18 to 30 or more, depending on the ty p e and size of the plant. These plates act as de- phlegm ators, each one con stan tly condensing the products of higher boiling points, p erm itting the products of low er boiling points to proceed upw ard.

W hen the vapors leave the top of the still th e y enter a series of condensers, in some typ es, called a “ goose,”

which consists of a series of pipes arranged v e ry much like a radiator. These pipes are surrounded b y cooling w ater a t a tem perature p ractica lly one degree higher

1 P u b lish e d b y a u th o r ity of th e C o m m issio n er of I n te rn a l R ev e n u e . See co m p an io n a rtic le , “ T h e D istilla tio n of W h isk e y ," Th i s Jo u r n a l, F e b ., 1910.

than the boiling point of e th y l alcohol. The purpose of th is apparatus is to condense all products as far as possible, w hich boil a t a higher tem perature than eth yl alcohol and which have escaped the action of the plates in the still. From the “ goose” the vapors pass into the condenser. In recent years, on accoun t of the excessive w eight of the “ goose,” w hich in some distilleries is a tan k as large as a good-sized room, a sim pler apparatus has been devised, called a “ tub ular sep arato r;” this operates on the same principle as th e “ goose,” nam ely, is cooled b y w ater a t the same tem perature. This is considered b y m an y to be as efficient a piece of apparatus.

A t the “ tail b o x ” or end of the condenser, the dis­

tillate is separated into various fractions, depending on the q u ality, b y the operator of the still. These are generally called, in the order distilled, “ fore- sh ots,” or low wines, “ heads,” “ m iddle run ,” “ ta ils,”

“ low w in es” and lastly, “ fusel o il.” The point at which the different fractions are cut out depends upon the class of goods desired b y the operator. The

“ middle ru n ” is the cleanest p art of the distillation, and when a v e ry clean spirit is desired is freq u en tly separated in a No. 1 and a No. 2 spirit. T h e “ fore­

shots” and low wines are the poorest p arts of the run, containing the greatest am ount of bad sm elling im purities, w hich render them unfit for com m ercial purposes. In this condition th e y are generally col­

lected for several days and then redistilled in the

“ colum n.” (The b etter p art of such a redistillation is classed as “ com m ercial alcohol.” ) The “ heads and ta ils,” if separated fairly clean, are com bined and called “ com m ercial alcoh ol.” The “ m iddle run ,”

No. 1 and No. 2 spirit go into the trade as such. The

“ fusel oil” is n ot run off a t the end of each charge b u t is perm itted to rem ain in the still and on the plates of the colum n u n til tw o or more charges h ave been run, when, in the jud gm en t of the distiller, sufficient

“ fusel o il” has been collected to w arran t its distilla­

tion ; this is conducted b y sim ply turn ing on more steam when the last of the “ low w ines” h ave been run from the charge then in the kettle.

T h e last portion of the “ low w ines” w ill consist of increasing proportions of fusel oil and w ater. W hen the per cent, of fusel oil is so great th a t it does not rem ain in solution, the flow in the tail b o x becom es m ilky, and the subsequent distillate is distilled into the “ fusel o il” tank. The fusel oil is g ra d u a lly forced up the colum n from p late to plate, being carried u p ­ w ard b y “ steam distillation .” A lth ough w ater is of a low er boiling point than the a m y l alcohols, y e t it does rem ain on the plates o f.th e colum n after the fusel oil has been driven up.- This can be proven b y opening the tr y cocks a t each p late in the still during the course of the distillation.

M E T H O D S O F A N A L Y S IS .

T h e a n a lytical m ethods used were those as found in B ulletin 107, B ureau of Chem istry, D epartm ent of A griculture, under “ D istilled L iq u o rs,” w ith changes in treatm en t for esters and higher alcohols.

Proof.— T h e proof of the sam ples w as determ ined