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B y He r m a n nC. Ly t h g o ba n d Le w i sI . Nu r b n b e r g. R eceiv ed O ctob er 14, 1908.

I t is a w ell-know n fa c t th at m ilk serum is of more uniform com position th an m ilk, consequently its constants, p articu larly the specific g ra v ity have been used fo r m an y years for the detection of added w ater. R ecen tly the in d ex of refraction has been suggested for this purpose and was first em ployed b y V illiers and B e rta u lt1 in 1898 w ho prepared the serum b y placin g a m ixture of tw o volum es of 1 per cent, acetic acid and one volum e

’ B ull. Soc. Chim., 19, 305.

of m ilk in a flask connected w ith a reflux condenser, heating to the boiling point, cooling and filtering.

T h e serum w as exam ined in the oleo-refractom eter of A m a g a t and Jean. M atthes and M üller1 in 1903 first suggested the use of the Zeiss im mersion refractom eter for this purpose, using the serum obtained from spontaneously soured m ilk. Leach and L y th g o e 2 in 1904 prepared the serum according to the m ethod of W oodm an3 w ith 25 per cent, acetic acid, tak in g the refraction w ith the immersion refractom eter. B aier and N eum ann4 m ixed the m ilk w ith an asaprol citric acid solution in th e cold, filtered, and determ ined the in dex of refraction of the filtrate w ith the W olln y m ilk fa t refractom ­ eter. A ckerm an5 heated the m ilk w ith a calcium chloride solution and determ ined the in dex of refraction of the serum b y m eans of the im m ersion refractom eter.

D uring the past tw o years m any sam ples of m ilk of know n p u rity have been exam ined in the lab ora­

to ry of food and drug inspection of the Mass. S ta te B oard of H ealth to w hich tw o or m ore of the above m ethods h ave been applied. T h e specific gravities of the sera were obtained a t 1 5 0, and the indexes of refraction on the im m ersion refractom eter a t 20°, and th e results are reported in the accom p an yin g tables. T h e sam ples of m ilk w ere all m ilked in the presence of an inspector or an a n alyst of this de­

partm ent.

T h e details of the m ethods used for the prep ara­

tion of the m ilk sera are as fo llo w s:

A cetic A c id Method.— T o 100 cc. of m ilk a t ab o u t 200 C. add 2 cc. of 25 per cent, acetic acid, m ix w ell and place in a w ater b ath a t 70° C. for 20 m inutes. Cool 10 m inutes in ice w ater and filter.

Natural Souring Method.— A llow the sam ples to sour spontaneously and filter off the serum.

Calcium Chloride Method.— T h e details h ave been sligh tly modified from the m ethod of A ckerm an indicated above. P lace 90 cc. of m ilk in a flask, add 0.75 cc. of calcium chloride solution, sp. gr.

I -I 375 (when diluted 1: 10 this solution reads 26 on the im m ersion refractom eter a t 17.6 ° C.), shake thoroughly, close the flask w ith a cork carryin g a glass tub e to a ct as a reflux condenser, place in a boiling w ater b ath for 20 m inutes, cool to 20°, m ix th e condensed w ater and serum w ith ou t shaking, and filter.

1 Z eit, offentl. Chem., 10, 173.

1 J . A m . Chem. S oc., 26, 1195.

* Ibid., 21, 503.

4 Z eit. N a h t-Genus sm., 13, 369.

* Ibid., 14, 186.

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 . 39

---A c c tic

tion a t low temperatures, especially when inflammable vapors are given off, the tem perature being regulated b y raising or lowering the source of heat.

T h e use of electricity for boiling the solvent during ex­

traction gives a com pact apparatus, everything being on

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 . 41

tinuously through the night, no attention being required after first regulating the flow of condensed solvent.

E . O . Th o m a s.

tribute to applicants samples of an analyzed argillaceous limestone1 suitable for the m anufacture of Portland cement. any standard samples are ready for distribution.

The Bureau also calibrates volum etric apparatus, for a small charge, provided the pieces have identification marks and conform in other respects to the B ureau’s requirements.

tional Fertilizer Association on the analysis of phosphate rock has just been issued. The com m ittee which was ap ­ pointed early in the year b y the Association consisted of Messrs. C. F . H agedom , C. H . Dempwolf, Jr., and F. B.

1 Jour. A m . Chem. S oc.. 2 8 , 229.

Carpenter, all well-known chemists connected with large fertilizer interests. The essential features of the report, w ith the exception of the names of the analysts, follow:

To the Members of the National Fertilizer Association:

The discrepancies between the results of chemists in the analysis of phosphate rock have often been the cause of disputes between buyer and seller, sometimes resulting in costly litigation, and usually ending in a feeling of dimin­ our Association of methods which will yield uniform results

F our sets of samples of the following kinds of phosphate rock were prepared: Tennessee Brown, Tennessee Blue, South Carolina and Florida. These were distributed among the chemists of our Association and the commercial chem­

ists who make a specialty of fertilizer analyses. E ach chem ist was instructed to determ ine moisture, phosphoric acid (also calculated to calcium phosphate) and iron and aluminum oxides, using the routine method of his labora­

tory and to return a com plete report of the results, together w ith a copy of his methods.

Thirty-one reports were received, which we have classi­

fied according to methods, giving in each case a brief out­

line of the method. Below each table we have also noted the im portant modifications of these methods.

MOISTURE.

N o. 1 N o. 2 N o. 3 0-6397, the theoretically correct factor being 0.63757, al­

though 0.6376 is close enough.

Volumetric Method, sometimes called Pemberton’s Method.

— T h e solution of the yellow precipitate in standard potas­ of phosphoric acid as ammonium magnesium phosphate.

Described fully in W iley’s “ Principles and Practice of A gri­

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 . 43 which com pletely precipitates the iron and aluminum phos­

phates. This is dissolved in H C1 and reprecipitated in the

line precipitates the iron and aluminum as phosphates.

A nalyst. N o. 1. N o. 2. N o. 3. N o. 4.

Jones Variation of Glaser Method.This is p ractically the same as the Glaser method, except th at about % the

Wyatt's Method.T he phosphates of iron and aluminum are precipitated from a portion of the original solution b y

EFFECT OF DIFFERENT SOLVENTS IN THE DETERMINATION OF IRON AND ALUMINA.

W e have received from Messrs. L. P. Brown and Com­

pany, Nashville, Tenn., an interesting comparison showing the effect of different solvents in the determ ination of iron remains undecomposed when hydrochloric acid is used.

T h e effect of aqua regia as a solvent can also be seen in several of the tables under iron and alumina, especially in the case

44 thorough investigation failed to detect any. A ccordingly, tests were made on tomatoes-, both green and ripe, fresh the following products for the constituents named, definitions to be decided upon when necessary: F ats and oils, moisture acids, moisture, combined alkali, free alkali, m atter insoluble in alcohol, sodium chloride, unsaponifiable m atter; Crude Glycerine, glycerol, organic im purities; D ynam ite Glycerine, specific gravity, organic residue, sodium chloride, ash, fa tty acids, silver nitrate test; Chem ically Pure Glycerine, con­

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 . 45

sideration of methods postponed for the present. The follow­

ing special com m ittees were appointed to consider the various subdivisions of the main subject: F ats and Oils, Mr. Loveland, chairman, and Mr. R ich ard son ; Cotton Seed Foots and Cotton Seed B lack Grease, Mr. Wesson, chairman, and Mr. Tw itchell;

Cotton Seed Foots Soap, Mr. Low, chairman, and Mr. Wesson;

Crude and D ynam ite Glycerine, Mr. Langm uir, chairman, Mr. Devine and Mr. H yde. The general plan of procedure includes the consideration of the best methods a t present in use for the various determ inations and co-operative work on standard samples b y analysts skilled in the various lines of work using the methods selected; the form ulating of definitions of words requiring definition; and the drawing up of standard m ethods of analysis.

All analysts who are interested in the work or who are will­

ing to co-operate in it are invited to correspond with the chairmen of the special committees, or with the chairman of the subcommittee. W . D. Ri c h a r d s o n.

Q U O TATIO N S.

CH ILEAN N ITR A T E FIELD S.

(F rom D a ily Consular and Trade Report, N o. 3327, N o v . 10, 190S.) The following report concerning the nitrate fields of Chile, and the manner of producing nitrate of soda and iodine, is furnished b y Consul R ea H anna, of Iquique:

The Camarrones V alley, in latitude 190 south, marks the northern lim it of an y appreciable deposits of nitrate, and Carizal V alley, in latitude 26° south, marks the southern limit. W ithin this zone, which has a length of some 500 miles, deposits of salitre, or nitrate of soda, have been dis­

covered in five different districts as follows, running from north to south: (1) T h e pam pa of Tarapacd, included between south latitudes 180 30' and 2 10, with the ports of Iquique, Caleta Buena, Junin, and Pisagua, and a railw ay running from Iquique, to Pisagua, connecting all the impor­

tan t nitrate plants; (2) the pam pa of Toco, on the banks of the small river Loa, which furnishes power for some of the plants, in latitude 220 south, with the port of Toco- pilla, and a railw ay to the principal nitrate works; (3) the pampa of Antofagasta, in latitude 230 south, traversed b y the railway from A ntofagasta, the port, to Oruro, Bolivia;

(4) the pam pa of A guas Blancas, in latitude 240 south, with the port of Caleta Coloso; (5) the T altal Pam pa, be­

tween south latitudes 250 and 26°, with the port of T altal.

Crystallized nitrates appear in very small quantities only, being found in com m ercially valuable am ounts in a m ix­

ture of chlorides, sulphates, and other salts, together with earth and rock, com m only called caliche.

In technical works on this subject, the local names of the strata are usually employed. T h e accom panying sketch gives an idea of the average form ation in the Pam pa of Tarapacd, which is the most im portant of the nitrate fields.

STRATA IN WHICH N ITRATE IS FORMED.

The ‘‘chuca” is a loose layer of from 8 to 16 inches in thickness, and is composed, generally speaking, of decom­

posed volcanic rock.

The "costra” is a m ixture of feldspar and other similar rocks or the clay and sand products of their disintegration, together with sulphates of calcium, sodium, and potassium,

and chloride of sodium, and is from 3 to 10 feet in thickness.

I t is never less than 1 foot thick and never more than 18 or 20 feet. I t is composed o f the same materials as the chuca, w ith the addition of salts which a ct as cement, making it v e ry hard in places. The composition is principally of clay, salt, nitrate of soda, and sulphates of magnesium, calcium, and sodium.

T he caliche, with the exception of very rich lays, is, like the costra, a m ixture of detritus united b y a cement of salts.

The insoluble constituents of caliche are fragm ents of vo l­

canic rock and quartz gravel, from the size of fine sand to pieces as large as a human head. Caliche is a general term applied to all classes of m aterials containing nitrate, and varies greatly from a chemical standpoint; it is the cus­

tom ary term for the material taken from the strata rich in nitrate.

GROUPS AND COMPOSITION.

On account of its form ation and origin it m ay be classed under four headings:

(1) In the form of deposits in strata, in veins, and in pock­

ets resting on loose material and quaternary detritus, and covered with a layer of conglomerate salts, gravel, and loose earth, these strata measuring from 8 inches to 26 feet in thickness.

(2) In the form of impregnations which the nitrate and its accom panying salts have left in the decomposed sur­

faces of volcanic rock.

(3) In the form of fillings in chalky deposits.

(4) In the form of efflorescence on the surface of salt fields.

O f these four groups the first one is the only form having im portance in the production of nitrate.

There is a great variation in the composition of caliche as well as in the appearance, and the nitrate of soda con­

tained runs from 15 per c e n t to 65 per cent, of the total weight, the average running from 25 per cent, to 35 per cent.

Chloride of sodium is alw ays present and a t times is found in banks as pure crystalline salt.

IODINE, CONGELO, AND COBA.

Iodine is the im portant by-product and occurs as iodate of calcium, called "lau rita,” and a double salt composed of iodate of calcium and chrom ate of sodium, called "diet- zeita.” These are the most im portant form s; the iodides do not appear. The existence of chromic acid gives the caliche an orange color and indicates a high la y of iodine.

T h e proportion of iodine runs from 0.06 per cent, to about 5 per cent., 2 per cent, being considered a favorable amount.

T he “ congelo” is found in varyin g quantities in all dis­

tricts, and consists of a substance containing com pact crys­

talline masses of chloride of sodium, of iodine, or of sul­

phates.

T he “ coba” is, as a rule, loose earth slightly moist, mixed w ith small rocks or pebbles. Salitre and other salts are contained in v e ry small quantities. The coba rests on vol­

canic rock, and in places has a thickness of 300 feet.

The nitrate district is situated in the rainless belt, and although h eavy fogs are often present it seldom rains.

EXTRACTION OF NITRATE OF SODA.

Before beginning actual work in the calicheras, or areas of deposit o f the caliche, an exploration is made b y means of drilling to find the lim its of the area of ground rich in

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 . the oversaturated solution b y means of crystallization.

In spite of the fa c t th at this process appears mechanically simple, the practical application presents m any difficulties.

s o l u b i l i t y a n d b o i l i n g. Commercial usage calls everything salitre, except moisture and insolubles. in general, to produce from 50,000 to 100,000 Spanish quintals (1 quintal = 101.61 pounds) per month the plant in vest­

chinery, $266,700; mules, harness, carts, merchandise for store, sacks, coal, etc., $133,150; total, $445,290.

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 . , 47 Patnpa, 740,000,000; Antofagasta, Toco, and T altal pampas, 4,103,000,000. T otal, 4,843,000,000.

m a r k e t i n g t h e o u t p u t.

The Antofagasta Painpa was expected to develop rich deposits, and h eavy investm ents were made in the matter of extraction plants, but exploitation discovered that instead of lying in regular strata, as in Tarapaca, the caliche is de­

men. The success of this scheme depends on the continuance of the present nitrate combination, which terminates, ac­

cording to the agreem ent a t its form ation, on March 31, 1909. colloidal aqueous solution (hydrosol). Subsequently the senior author dem onstrated3 that this liquid, in presence of hydrogen, was capable of causing the catalytic reduction of nitrobenzene. The work has now been extended to in­

clude certain other substances,3 the most generally interesting of which are oleic acid and a number of oils.4

The acid, in the form of its potassium salt, is dissolved in water and mixed with a small qu an tity of the palladium solution, the liquid being then introduced into a gas burette containing hydrogen, standing over mercury. Absorption of the gas commences im m ediately and the reaction is com ­ pleted in a few hours. No heating is required. Oleic acid, under these conditions, is converted alm ost quantita­

tively into stearic acid. Castor oil, dissolved in a mixture physiologists, because the reactions proceed under con­

ditions comparable, in a number of respects, with those under which similar or identical products are formed in nature.

To the industrial chemists, the results m ay also prove to (Carthamus tinctorius); spanwood, or bakam (Caesalpinia sappair); palas (B utea frondosa); annatto, Orleans, or lakkam (B ixa orellana); majisto (Rubia cord ifolia); kam ala (Mallotus philippinensis); singher, or harsinghar (N yctanthes arbor-tristis); jackwood, jack, or kanthal (Artocarpas integrifolia), and lac dye. obtained are frequently considerably faster on silk than on cotton. This, taken in conjunction with the fact that m any of the commonly used synthetic dyes do not give fast dyeings on silk, causes the indigenous dyes to compare much more favorably with their synthetic adversaries in this field than was the case of the field of cotton dyeing. dyestufls used for comparison only 4, viz., alizarine, primuline, chrysophenine, and magdala red are capable of yielding dye­

48

in this respect. In fact, the general fastness of lac dyeings made it appear to me a m atter of surprise that this material has been so com pletely superseded b y synthetic dyes, the more so as it is necessarily obtained as a by-product in the purifi­ ties, which are now in course of construction. A few thousand of such ties, ordered for experim ental purposes, were con­ specifications respecting the furnishing of ties of reenforced cement to the Italian state railways: eight days under water, must show a coefficient of resistance to strain of not less than 10 kilos per square meter and a co­ fresh water is again applied it will be found to remain perfectly clear.

selves that the conditions of these specifications are observed, and will therefore have the right of free entrance to the under m anufacture will be rejected.

T h e furnishing firm is required to guarantee the ties for one year from the date of the last receipt of consignment and to replace or refund the price of any ties which it has become necessary to remove during the period of gu aranty because of their unserviceable nature, resulting from de­

fective m anufacture; and action in this regard is to be left to the exclusive judgm ent of the administration of the state railways.

Diagram s showing the detailed Italian construction and m anufacture and test of concrete railw ay ties m ay be seen a t the Bureau of Manufactures.

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 . 49

The book is divided up into chapters as follows: I. Physical Properties of the Metals, 9 pages. II. R efractory Materials Iron, Steel, Crucible, Bessemer and Open-Hearth, Further Treatment, 93 pages. X V I I . - X I X . Copper, etc. R ever- beratory, B last Furnace and P yritic Smelting. W et Methods.

Copper Refining, 39 pages. X X . - X X I I . Lead, Ores, etc. compass requires great condensation and a careful elimination of all but the essentials. T his has been done b y Mr. W ysor points are m ostly those of Roberts-Austen’s "Introduction to Metallurgy.” This could have been im proved by introducing the later and more accurate determ inations of Burgess and others. The few lines devoted to hardening carbon on p. 17 are quite misleading. On the same page we are told that silicon combines with iron probably in several proportions, whereas it would have been as easy and better to have bearing the proper relationship to their relative im portance;

the difference between uses of the reverberatory smelter (or barrel process, which for years was the main method onCripple Creek Ores, is neglected. In the cyanide process the space earlier methods, with the remedies and improvements receiv­

ing m arked attention. Costs of production are given through­

out and these are so fu lly item ized th at possibilities of cost electrom etallurgical industries in these countries, and the hope is expressed th at with the utilization of the waste gases of blast furnaces for production of electric current, the iron centers of these countries m ay also become centers of electro­

m etallurgical industry. On pages 116 and 117 it is stated th at “ the anode copper used in these two refineries (Anaconda and G reat Falls) is p ractically the same in composition, since it is obtained b y sm elting the ores of the famous mines of the

m etallurgical industry. On pages 116 and 117 it is stated th at “ the anode copper used in these two refineries (Anaconda and G reat Falls) is p ractically the same in composition, since it is obtained b y sm elting the ores of the famous mines of the

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