Any pharmacist would be enabled to use the tests, and would be much more likely to use them, than if special apparatus had to be employed. It is believed that the results obtained would be equally satisfactory.

Many of the burettes and graduated vessels made for volumetric purposes, are incorrectly marked, and hence are worse than useless, because they mislead those who rely upon their accuracy; and it is feared that many pharmacists into whose hands they may come, have not the experience or skill to verify their instruments.

These suggestions were brought before the Committee of Revision of the Pharmacopoeia, and upon a vote being taken, the following was the result: Four voted to introduce this process to the exclusion of the volumetric process; seven voted to introduce it alongside of the volumetric process, while twelve voted not to admit it; and it was therefore rejected.

Notwithstanding this decision, it is believed that time will show its availability and superiority, and that in the near future it will be admitted.

It has been objected to the scheme, that accurate scales and weights would be required; this is true, but these are already required to make the standard solutions used in the volumetric process, the solid ingredients of which must be carefully and accurately weighed.

The name Stathmetometric (derived from the Greek words "oraÐμNTOS " -weighed, and "μETPIKOS" pertaining to measure), has been applied to this method of testing.

Although we speak of things being measured by weight, we generally use the terms " weights" and "measures" as meaning specific and distinct subjects, the word "measure" being usually restricted in its application to length or distance, and to size or capacity; for this reason the term "metric" as applied to determination by weight, is not entirely appropriate; besides which the term "metric" has a special significance, with which the scheme of testing has no necessary connection.

66

I have, therefore, suggested in place of "stathmetometric," the term "stathmetic," from the Greek word "σrafμeriкKoç," pertaining to weighing, a word which is more easily uttered, and which is as completely significant as the longer word.

I would respectfully ask the members of this Association to give the Volumetric and Stathmetic processes a comparative trial, and report the results of their experience at the next annual meeting.

III. MATERIA MEDICA.

CAFFEINE IN COMMERCIAL POWDERED GUARANA.*

BY J. H. FEEMSTER, CINCINNATI.

Query 48.

"What is the proportion of Caffeine in the Powdered Guarana of Commerce."

That adulteration is commonly practised, not only in medicinal drugs, but also among articles of every-day consumption as food, has been abundantly proven by investigation made by those who are eminently fitted for such work.

With the results of these investigations in mind, I was prepared in accepting this query, to find that Guarana in the process of powdering, was contaminated with some inert substance foreign to the drug.

I have, after analyzing five samples (of five hundred grains each), procured from as many different sources, been most agreeably surprised to find the proportion of caffeine so large in each specimen, that the idea of adulteration is precluded.

The results as appended, were secured by the process of Prof. E. S. Wayne, as mentioned in my answer to query No. 30 "On Caffeine in the Guarana of Commerce." (Proceedings Am. Phar. Assn., 1882, page 569).

No. I yielded 211⁄2 grains Caffeine, or 4.3 per cent.

No. 5 yielded 25 grains Caffeine, or 5 per cent. The total yield from the five specimens was one hundred and eighteen grains, (118) and the average, twenty-three and six-tenths (23.6) grains, or four and seventy-two hundreths (4.72) per cent.

The above percentages are greater than those resulting from the analyses made on the crude Guarana as reported last year, and I can only account for the difference by supposing that the drug was dried to some extent before powdering. Be this as it may, however, the results, as above reported, are sufficient to lead to the conclusion that the samples analyzed were not adulterated, and to encourage us to the belief that the reports that have been made during the several years past on adulterations, have been of some effect.

*Read at the Sixth Session.

ON OIL OF BIRCH BARK AND OIL OF WINTER

GREEN.*

BY GEO. W. KENNEDY.

Query No. 41.

"Is oil of birch bark sold in commerce under the name of oil of wintergreen?"

Before answering the query, I will furnish a little information on this subject, which, no doubt, will be of some interest to the profession.

It is well known that little has been done for almost forty years towards determining the true chemical composition of oil of birch. Procter, in 1844, found it to contain salicylic acid, and to be almost identical with the oil of gaultheria; and from that time up to 1882, nothing was done till the writer made some experiments which proved the presence of sali-. cylic acid. I have two specimens here-one, the oil of birch, and the other, oil of gaultheria-which are known to be absolutely pure. You will observe whilst they both possess that strong and agreeable aromatic odor, and a sweetish aromatic taste, characteristic of both oils, yet by close comparison a difference can be perceived; this is another case where two oils obtained from different plants closely resemble each other. The same remarks apply to the oils obtained from Ceylon cinnamon and Chinese cinnamon, also the oils of Pimpinella anisum and Illicum anisatum. The sample of oil of birch was made last March; it was then colorless, but now has acquired a reddish color.

This year, Mr. H. P. Pettigrew, a student at the Philadelphia College of Pharmacy, made a thorough investigation of the oil, which can be found in the August number of the American Journal of Pharmacy, the results of which are briefly summarized as follows:

Ist, The volatile oil of birch is not identical with the oil of gaultheria in that it consists entirely of salicylate of methyl, and contains no terpene.

2d. The specific gravity of oil of gaultheria is not 1.180, as stated in the United States Pharmacopoeia, but 1.0318, the former being the sp. qr. of oil of birch, which as is known is often indiscriminately sold and employed as oil of gaultheria.

Mr. Pettigrew evidently made a very careful and creditable analysis. of the oil, but failing to discover a terpene, Prof. Maisch induced the writer to investigate the process more carefully by which the oil of gaultheria is obtained, believing that the hydrocarbon was washed away during the manufacture of the oil. This supposition proves to be correct, as

* Read at the Fourth Session.

I soon detected the mistake of the distillers, by which the terpene is lost, which I shall explain further on.

In my paper on oil of birch, published in the American Journal of Pharmacy, 1882, page 49, I gave a concise description of how the oil is extracted, a portion of which I here repeat: "The material being ready for distillation, is placed in the still, as much as this will hold, and a sufficient quantity of water is added to fill the still about onethird full. The still is generally permitted to remain in this condition over night, a fire is made in the morning, and distillation proceeds nicely. The condensers used are of two kinds, one being the ordinary copper worm placed in a large barrel, while the other is made of copper pipe, about 2 inches in diameter, and shaped like the letter U, each wing being 122 feet long, and placed in a trough. A stream of cold water is constantly passing into the barrel and trough, which is carried several hundred feet by a wooden gutter, from a creek of clear spring water. The condensed steam in the condenser consists of water and oil. The Ushaped condenser, the distiller says, is more desirable than the other, because the first portion of distillate contains oil, whilst in the old worm style several bucketfuls of water pass out before a drop of oil makes its appearance. As the liquid comes from the condenser, a novel contrivance is used for collecting the oil and water, consisting of a Mason's fruit jar (large size) complete; a small tin funnel is placed in the metallic cap of the jar at one side, and extends below the cap; the condensed liquid runs through the funnel into the jar, and as the weight of the oil is greater than that of the water, it sinks to the bottom of the receiving vessel. The water runs out through a pipe fastened into the cap on the side opposite to that where the funnel is inserted, is conducted into a bucket, and finally emptied into a barrel, to be used again for the next lot of material. The same plan is carried out at nearly all the distilleries.

You will at once see the defect in the distillation. The distiller collects that portion which falls to the bottom of the vessel, which is no doubt exclusively salicylate of methyl (methyl salicylic ether), the light terpene separating and floating on the surface of the water in drops; this is known as "light oil," and "light ring." No care is taken to collect

it, and it is nearly all washed away or lost. I communicated with a number of distillers on this subject, asking them if they had ever noticed a light substance on the top of the water, and the reply was always the same, that they had, and that they never took any pains to save it, not knowing it had any value. This would explain why Mr. Pettigrew failed to get any terpene. Judging from the quantity which separates, as explained to me, the oil may contain as much as the oil of gaultheria, about 10 per cent.

In this locality, the oil of gaultheria is made in a similar manner as

the oil of birch, and I presume upon examination it will be found lacking in gaultherilene.

The sample spoken of by Mr. Pettigrew, in Mr. Maisch's possession, came from me, and I have every reason to believe it strictly pure-its low specific gravity would also indicate that it contains the hydrocarbon. The two samples on the table, you will observe, are of about the same specific gravity; oil of gaultheria is 1.181 at 84° F., the oil of birch 1.180 at the same temperature.

Old leaves of gaultheria do not yield as much oil as new leaves. Old leaves on plants that have never been picked yield approximately 12 oz. to 100 pounds of the leaves. Spring leaves, or leaves gathered in the spring, from plants that have been previously picked twice a year, in the spring and towards fall, yield about 14 ozs. to 100 pounds of the leaves. Again, the leaves gathered in September from first year's plants yield as much as a pound from 100 pounds of the leaves.

Returning to the query, I would answer, yes; the oils of birch and wintergreen are mixed, sold and used indiscriminately as oil of gaultheria. Enormous quantities are made in Schuylkill county, Pa., and the few adjoining counties; one would wonder for what purpose it is all consumed and where it all goes. In the counties of Carbon and Monroe there was not less than twenty tons made last year, and from present indications that quantity will be reached this year. The amount of oil of birch distilled is estimated at 40 per cent. Bradford, Sullivan and Susquehanna counties make about two tons annually, about 10 per cent. of which is oil of wintergreen. Schuylkill county makes about 1000 lbs., of which about 10 per cent. is oil of wintergreen. In the first two counties the leaf (teaberry) grows more abundantly; that accounts for the larger percentage of the oil.

[NOTE. After the meeting, when the distillation of the oil of birch had been commenced, the writer had occasion to examine some of the "light oil" spoken of, and found it to be methyl salicylate adhering to chips of wood, and floating upon the condensed water; the oil was free from hydrocarbon.]