Examination of Commercial Black Antimony, 
Tartar Emetic, and Glycerin. 
Papers presented to the 33d Annual Meeting of 
the American Pharmaceutical Association, at 
Pittsburgh, Pa., September, 1885. 
BY 
ROBERT B. WARDER, 
PROFESSOR OF CHEMISTRY IN THE SCHOOL OF 
PHARMACY AT LAFAYETTE, IND. Reprinted from the Proceedings of the 33d Annual Meeting of the American Pharmaceutical Association. 
BLACK ANTIMONY OF COMMERCE.* 
ROBERT B. WARDER. 
Query No. 84.- What is black antimony of commerce ? 
The term "black antimony" is sometimes applied to the powdered 
metal, as in Roscoe & Schorlemmer's Treatise on Chemistry, Vol. II., 
part ii., p. oo6; but in pharmacy it is supposed to mean the powdered 
stibnite or native sulphide. 
Fifteen samples were procured from as many retail druggists in eastern 
cities and the central states; and it soon became evident that the name is 
used in very different senses in the two sections of the country. The 
"pure antimony black" of the price lists is the genuine stibnite in a 
powdered form-there is no evidence that it has been purified; " commer- 
cial antimony black," on the other hand, is an utterly spurious imitation 
of the same, yielding no trace of antimony by the tests of the Pharma- 
copceia. 
The following table shows the localities where the several samples were 
procured, and the reaction of the two kinds: 
1. Cincinnati, Ohio. 
2. " 
3. Chicago, Ill. 
4- 
5. Ypsilanti, Mich. 
6. Indianapolis, Ind. 
7. Lafayette, Ind. 
8. Vincennes, Ind. 
9. 
HC1 dissolved a portion of each sample (usually with 
violent effervescence in the cold), leaving considerable 
black residue. There was no evolution of H2S, and 
no traces of antimony could be detected in the solutions 
by means of water or H2S. Specific gravity of the pow- 
der, including air spaces, about 1.25. 
10. Boston, Mass. 
II. " 
12. New York, N. Y. 
13. Philadelphia, Pa. 
14. 
15. 
HC1 dissolved each sample (except a small residue), 
with moderate effervescence of H2S. Each solution 
gave a heavy white precipitate by dilution with water, 
soluble in tartaric acid. H2S re-precipitated orange 
Sb2S3. 
The appearance of these two substances is different enough when seen 
side by side, especially when observed with a lens. Powdered stibnite 
(Nos. io to 15) is inclined toward a bluish red color, with almost me- 
tallic lustre, suggestive of ground galena. No. 14 was very finely pow- 
dered. and appeared less lustrous unless pressed with a knife blade. Nos. 
1 to 9 have a duller appearance of iron grey : the contrast with stibnite 
* Presented at the Fourth Session. 2 
gives the impression of a reddish tinge. With a pocket lens, however, 
the larger particles shine with a black resinous lustre like anthracite coal. 
No. i was unchanged by heating in a closed tube, and effervesced in the 
cold with HC1, leaving a black residue that burned with difficulty to a 
whitish ash. The acid solution contained both calcium and magnesium. 
A partial separation was made by simple elutriation, the black particles 
being washed off, while a white translucent powder was left. This 
effervesced with cold dilute HC1, and dissolved almost entirely on boil- 
ing. Sample No. i seems to have been made by mixing powdered 
anthracite with marble or magnesium limestone. Detailed analyses were 
not made of the remaining samples, except as indicated in the foregoing 
table; but they are all essentially like No. i. Paper moistened with 
solution of lead acetate was used in each case, to test for traces of 
hydrogen sulphide. A bottle holding one ounce of water will hold 2}^ 
ounces of powdered stibnite (when well shaken together without pres- 
sure), but only ounces of the imitation. This may afford a conven- 
ient mode of distinguishing between them, for those who do not wish to 
apply the chemical tests. In fact, the difference of specific gravity is so 
great, that any one accustomed to handle packages of such drugs would 
instantly suspect the spurious article from its greater bulk. A certain 
dealer is said to have defended his sales of the coal dust on the ground 
that genuine black antimony " kill all the stock in the country." 
It is not the purpose of this paper to discuss moral questions; but it 
would be a great convenience to avoid ambiguity by calling coal and 
limestone by their own names. 
TARTAR EMETIC OF COMMERCE.* 
Query No. 68.- What is the quality of commercial tartar emetic ? 
BY ROBT. B. WARDER. 
Thirteen samples were procured from as many retail druggists in var- 
ious cities. The ready solubility in water indicated the absence of nota- 
ble quantities of acid potassium tartrate; but two specimens left a pulveru- 
lent residue, probably of antimonious oxide. Eight specimens contained 
at least traces of calcium, but only one contained traces of sulphate, while 
chlorides and iron were wholly absent, and any possible traces of arsenic 
were too small to be shown by Fleitman's test. 
This drug is usually nearly pure, calcium salt being the chief impurity. 
This could easily be introduced with the acid potassium tartrate used in 
manufacture, and would seldom lead to injurious results. Details are 
given in the table below: 
* Presented at the fourth Session. 3 
No. 
Locality. 
Action with 
water. 
With Am20x. 
With BaCl2 
and HC1. 
i 
Cincinnati, O .. . 
Soluble. 
Precipitate on 
standing. 
Clear. 
2 
Chicago, Ill . . . 
Soluble. 
Clear. 
Clear. 
3 
White resi- 
due. 
Precipitate. 
Clear. 
No indication in 
4 
Ypsilanti, Mich. . 
Soluble. 
Precipitate. 
Clear. 
any of the samples 
5 
Indianapolis, Ind. 
White resi- 
due. 
Precipitate. 
Clear. 
of chlorides with 
- AgNO3, of iron, 
etc., with K4Fdy, 
nor of arsenic by 
Fleitman's test. 
6 
Lafayette, Ind . . 
Soluble. 
Precipitate. 
Clear. 
7 
Vincennes, Ind. . 
Soluble. 
Marked pre- 
cipitate. 
Slight pre- 
cipitate. 
8 
Vincennes, Ind. . 
Soluble. 
Clear. 
Clear. 
9 
Boston, Mass . . 
Soluble. 
Slight precip- 
itate. 
Clear. 
IO 
Boston, Mass . . 
Soluble. 
Clear. 
Clear. 
ii 
New York, N. Y. 
Soluble. 
Clear. 
Clear. 
12 
Philadelphia, Pa . 
Soluble. 
Marked pre- 
cipitate. 
Clear. 
13 
Philadelphia, Pa . 
Soluble. 
Clear. 
Clear. 
GLYCERIN OF COMMERCE.* 
Query No. 34.-How does the glycerin of commerce conform to the re- 
quirements of the Pharmacopoeia ? 
While the following paper was suggested by the query named, the pro* 
ducts of the principal American manufacturers have also been compared 
with each other and with samples from retail druggists of a few central 
cities. The French and German goods sold in the East have not been 
included, except, perhaps, in a single sample, No. 18, which was labeled 
"Sarg's C. P. glycerin." 
BY ROBT. B. WARDER. 
SAMPLES. 
Nos. i-12 represent the manufacturers, and were all procured from 
original packages in the hands of wholesale dealers, except No. 2 and No. 
10; these brands are in less frequent use than the rest, and samples were 
procured from the manufacturers, to save the expressage from distant 
places. No. 12 is a standard English brand, included for comparison. 
No. 3 and No. 12 are sold in pound bottles, at a much higher rate than 
most of the rest, which are sold in cans or casks. Nos. 13-20 were pro- 
cured from retail druggists. Every effort was made to have perfectly 
clean and dry bottles; but circumstances did not allow me to see to this 
personally in every case. 
* Presented at the Fourth Session. 4 
Each sample was a colorless, viscid liquid, except No. 4, which had a 
pale straw color. 
No odor was observed in the cold except in a single sample, which had 
the disagreeable, candle-like odor of crude glycerine. Personal observa- 
tion convinces me that the same brand is not usually so contaminated. 
When heated on the water-bath, with the addition of half a volume of 
water,* odors were observed in seven other samples-two of them 
were very slight. The retail samples averaged better in this respect than 
those representing the manufacturers. 
No butyric or other acidulous odors were developed by warming with 
an equal volume of dilute sulphuric acid. 
Very faint acid reaction was observed in some specimens after dilution 
with volume of water, but not sufficient in any case to redden litmus 
paper that was distinctly blue. Negative results were also obtained (after 
dilution with ten volumes of water) with blue paper slightly inclined to 
purple. A purple paper should have been prepared for the purpose, but 
this was omitted till it was too late. 
COLOR, ODOR, AND NEUTRALITY. 
The densities were determined by a specific gravity bottle, upon an 
accurate balance. Temperatures were noted (from 23.6° to 28. i° C.) and 
the density was calculated in each case for 15.50 C. by adding 0.0054 to 
the density found, for each degree Centigrade. The results are given in 
the table appended, and refer to the density of water at 4°C. It will be 
seen that only four samples are fully equal to the requirements of the 
Pharmacopoeia, while Mr. Kennedy's determinations as reported to the 
Pennsylvania Pharmaceutical Association in 1884, showed very little de- 
ficiency in this respect. The bottles were all kept tightly corked until the 
determinations were made; and although Nos. 1-15 were examined on a 
damp day, the neck of the bottle used was large enough to allow of 
prompt filling and discharge, and the moisture absorbed during manipu- 
lation must have been inconsiderable, f 
The bottle was carefully tested with distilled water. Reference to 
water at 15.50 C. instead of the maximum density, with the most liberal 
probable correction for the temperature of the glycerin, would scarcely 
add 0.002 to the densities reported. This margin of allowance would 
bring the majority within the limit 1.250; if the retail samples are diluted 
by five-tenths of one per cent, of water beyond the standard, this is as 
likely to arise from unavoidable circumstances as from intent or careless- 
SPECIFIC GRAVITY. 
* Mr. Kennedy recommends heating with the addition of water, but this is not 
required in the Pharmacopoeia. See "Proc. Penna. Pharm. Assoc." for 1884, p. 136. 
■{■Mr. Kennedy found that glycerine of 1.26 spec. grav. exposed to the atmosphere in 
an open flat jar absorbed 7% of moisture in seven days.- Proc. Amer. Pharm. Assoc., 
for 1879, p. 726. 5 
ness. Nos. 9 and 10 are not so high as we would expect from the claims 
■of the makers. 
ACRYLIC ACID, ETC. 
Special importance is attached by manufacturers to the test with silver 
nitrate for acrylic acid and similar impurities, arising from a partial de- 
composition of fats. The Pharmacopoeia states that there should be " no 
coloration," without specifying the time of action, nor the amount of ex- 
posure to light. Much care is required to secure absolute cleanliness in 
applying this test, as even traces of insensible perspiration from the fingers 
may invalidate the result. Twenty-two 2-drachm bottles with glass stop- 
pers were accordingly very thoroughly washed; the lip of each sample 
bottle was carefully wiped with paper and then rinsed with a portion of 
the glycerin itself to be thrown away, before pouring into the test bottles. 
The latter -were filled one-eighth full with the several samples; they were 
then filled half full with distilled water and well shaken, in order to 
diminish the viscosity, and facilitate the final mixing with the reagent. 
Each bottle was nearly filled with a five per cent, solution of silver nitrate, 
well shaken, and placed on white paper with uniform exposure to diffused 
light. The bottles were taken in order as numbered, and the last was in 
place five minutes after No. i had received the silver solution. Care was 
then taken to secure uniformity in the conditions. 
The last two test bottles were filled with silver nitrate and distilled 
water for purposes of comparison. The bottles were observed from time 
to time during five hours' exposure to ordinary daylight; afterward they 
were kept in the dark, and observed at intervals for fifteen days. The 
more important changes are noted in the table. There was no imme- 
diate change of color in any sample ; the promptness and speed of the 
deepening of color and formation of precipitate varied greatly. The ob- 
servations could have been rendered more accurate by providing a series 
of standard colors in similar bottles from permanent materials, with 
which to compare the silver solutions reduced by the glycerin from time 
to time. The terms used must be understood to be relative merely, for 
the manufacture of glycerin in this country has been brought to such a 
degree of perfection that what would usually be called a very slight reac- 
tion is recognized in this test as a distinct color. A reddish or violet 
test usually appeared after a longer or shorter time, changing to gray as 
the precipitates began to form. The only appearance of a distinct lead 
gray in No. 8 was quite exceptional. The several samples did not main- 
tain the same order of discoloration when observed at different times. 
Thus, after one or two hours, No. 12 was less limpid than No. 6 ; but 
after five hours the former seemed unchanged, while No. 6 was decidedly 
deeper. The amount of light present also has a very great influence ; 
one test exposed near a window to diffused light from the clear sky be- 
came about as dark in twenty minutes as a duplicate test which had been 6 
prepared two hours before, and which faced the interior of a well-lighted 
room, but was protected from the direct glare of the windows. No. 4 
had a decided precipitate after three hours; No. 10 had a smaller amount 
at the same time. Three samples only showed precipitate on the day of 
mixing; seventeen contained solid particles after three days; No. 12 
alone was free from precipitate after ten days, and a few little specks 
were seen in this after fifteen days. The blank test containing silver 
nitrate and distilled water remained perfectly limpid for ten days, and 
showed only the slightest discoloration at the time of the last observa- 
tion. This precaution was deemed needful to demonstrate the purity of 
the water used. The table shows considerable variation among the sev- 
eral brands, but no manufacturer should be condemned for the results of 
these experiments with single samples. Considerable variations among 
samples of the same brand have been noted. The requirements of the 
Pharmacopoeia should be more definitely stated in the next revision ; 
and if there should be sufficient demand for the utmost possible purity, 
an investigation should be made to determine the conditions needful to 
secure constant results-especially the influence of light, time, and excess 
of silver nitrate. With the present reading of the Pharmacopoeia, prob- 
ably not more than one of the samples would be condemned, as the ana- 
lyst does not usually think needful to wait more than a few minutes for a 
reaction to take place. The retail samples average quite as well as those 
representing manufacturers. 
Wholesale Druggists. 
No. 
Specific grav- 
ity. 
Color and precipitate with AgNO3 after 
y2 hour. 
I hour. 
2 hours. 
5 hours. 
3 days. 
10 days. 
I 
1.248 
I 
3 
4 
4 
C 
E 
2 
1-250 
I 
3 
3 
3 
B 
B 
3 
1-247 
I 
3 
4 
4 
C 
D 
4 
1.248 
4 
5 
7 
B 
E 
F 
5 
1-253 
1 
3 
4 
4 
C 
E 
6 
1.249 
1 
1 
1 
3 
B 
B 
7 
1.249 
1 
1 
1 
2 
A 
B 
8 
i-253 
1 
4 
6 
6 
C 
D 
9 
1.229 
1 
3 
4 
4 
C 
F 
IO 
1.244 
2 
4 
7 
B 
E 
F 
ii 
1-258 
1 
2 
3 
3 
A 
D 
12 
1.248 
1 
2 
2 
2 
A 
A 
Retail Druggists. 
13 
1-249 
1 
1 
2 
3 
C 
F 
U 
1.246 
1 
2 
2 
3 
B 
C 
IS 
1.248 
1 
3 
3 
3 
B 
C 
16 
1.246 
1 
4 
4 
4 
B 
B 
17 
1-247 
2 
4 
4 
4 
C 
D 
18 
1.246 • 
2 
4 
7 
B 
E 
F 
19 
1.248 
I 
3 
4 
4 
C 
F 
20 
1.246 
1 
2 
3 
3 
B 
C 7 
Explanation. 
Color. 
Precipitate, 
1. None. 
2. Almost clear. 
3. Very pale. 
4. Pale tinge. 
5. Pale violet. 
6. Grey. 
7. Distinct violet. 
A. None. 
B. Very slight. 
C. Slight. 
D. Medium. 
E. Considerable. 
F. Heavy. 
TESTS FOR SUGARS, ETC. 
i. Evaporation Test. The Pharmacopoeia requires that not more than 
a black stain shall remain when about two grams of the glycerin are 
heated to boiling in a small capsule on the sand-bath, and then ignited, 
while sugar leaves a porous coal. It may be assumed that the lamp is to 
be removed when the vapors are ignited, but this is not expressly stated. 
Variations in the intensity of the heat led to some misleading results, and 
the following plan was finally adopted: About two grams of glycerin 
were poured into a small platinum crucible, which was placed in an in- 
clined position (to facilitate access of air) deep in the sand-bath. When the 
liquid began to boil, the vapors were ignited and the lamp removed. The 
liquid then burned away to the last drop. Comparative tests were made 
with glycerin containing one-half per cent, of sugar, added as syrup to 
insure solution. In this case a considerable mass of porous black residue 
was always left. The samples of glycerin nearly always left something 
more than a 11 black stain there were traces of porous substance of yel- 
lowish brown to dark color, which quickly swelled and carbonized when 
exposed to the flame. The volume of this residue before carbonization, 
even when most abundant, was judged to be about one-third as great as 
the residue left under like circumstances by the same quantity of glycerin 
containing 0.5% cane sugar. 
2. Sulphuric Acid Test. The Pharmacopoeia requires that glycerin shall 
not become dark colored when warmed with an equal bulk of concen- 
trated sulphuric acid. Some preliminary experiments gave variations 
from a straw color to a deep amber with the same sample, on simply mix- 
ing the two fluids. Heating on the flame resulted in carbonization and 
frothing. Comparative tests were accordingly made with glycerin con- 
taining 0.5%, 1%, and 2% of cane sugar respectively; the first, when 
mixed with an equal volume of acid, became very dark colored, but was 
not quite opaque for some time. After a few hours it was black ; the sec- 
ond and third tests became black and opaque at once. 
Moderate variations in temperature may have marked influence upon 
the intensity of the reaction ; and experiments were therefore made to 
see how much variation was likely to result from differences in the relative 
amounts of glycerin and acid. Ten cubic centimeters of each at 240 C., 8 
rose to 970 C., on being mixed, showing an increase of 73° from the 
reaction. Five cc. glycerin mixed with 10 cc. acid rose to 98° C. Ten 
cc. glycerin with 5 cc.acid rose to 910 C. It thus appears that consider- 
able variations in the quantity of acid may produce little variation in the 
temperature, if the acid is in excess; but two 'iquids of such viscosity are 
liable to be imperfectly mixed in a test-tube, unless special care is taken. 
If an excess of acid remains in contact with the glycerin, it may first re- 
move the water, and then begin a process of carbonization. 
In several instances, where the liquids seemed to be thoroughly mixed, 
with the production of a straw color a darkening was observed near the 
bottom of the tube after some minutes, indicating that an excess of acid 
in that part had escaped thorough mixing. When no flame was applied 
to the mixture, a deep amber was the darkest color obtained; and this 
was characterized by strong fluorescence. The color in no case ap- 
proached that produced immediately by glycerin No. 6 containing 
0.5% of cane sugar. From these two tests we may safely conclude that 
no sugar or like materials had been added to any of the samples examined ; 
but either the destructive distillation of pure glycerin or its dehydration 
with sulphuric acid may yield traces of substances of higher molecular 
weight very similar in deportment to sugar. 
The use of Fehling's solution after prolonged boiling with acid, was 
considered superfluous for the object in view. 
MINERAL IMPURITIES AND OXALIC ACID. 
Diluted with ten volumes of water, each sample remained perfectly 
clear, with additions of barium chloride, calcium chloride, ammonium 
oxalate, and ammonium sulphide; sulphates, oxalates, calcium salts, and 
the heavy metals, are, therefore, absent. The residues left on evapora- 
tion were combustible, leaving no ash. 
The twenty samples tested conform very nearly to the requirements of 
the Pharmacopoeia, though a very slight excess of moisture is indicated 
in several instances; one sample had a very disagreeable odor; one also 
had some color, and gave distinct reaction with silver nitrate within half 
an hour The manufacturers maintain a high standard of excellences ; 
and retailers, so far as observed, do not adulterate the goods in their 
stores. It should be mentioned in this connection, however, that adul- 
terations are not unknown in the east. Cane sugar seems to be generally 
used for this purpose, since glucose is very readily detected by Fehling's 
solution. 
CONCLUSIONS. 
ACKNOWLEDGMENT. 
My sincere thanks are due to Prof. J. U. Lloyd, for many suggestions 
during the course of this investigation.