The specific gravity of the German Pharmacopoeia, 1.072-1.074, is not comparable with the above, because it is not the specific gravity of the bulked oil, but merely of eugenol, one of the heaviest constituents of the oil. The other pharmacopoeias do not state specific gravity requirements. A casual glance at the above table will reveal the fact that all the pharmacopoeias published before 1893, with two exceptions, Russian and Roumenian, require a low minimum specific gravity. The latter exception as to time, is no exception, however, as to requirement. With one exception, the pharmacopoeias published in 1893 and 1895 demand a higher minimum specific gravity. The Russian, although published in 1891, belongs in this class. The British pharmacopoeia, published in 1898, places its minimum requirement lower than the second class, but not as low as the first class of standards.

That these specific gravity requirements in a general way reflect the results of investigations of the periods represented will become apparent from the data enumerated in the following table. (See pp. 398-9). These are not all the data enumerated in the literature on the subject.

Changes in specific gravity due to differences in temperature were examined by Schreiner and Downer :

Corrections for differences of temperature can, therefore, be easily

made.

The following additional comments may be of some service.

In 1889, Schimmel & Co.† published the following statement: "According to our experience, the sp. gr. requirement of the Ph. G. II, viz., 1.041–1.060, is too low. We find 1.067 for clove oil, and 1.063 for clove-stem oil, both at 15°, whereas we have never observed so low a sp. gr. as 1.041 for clove oil from cloves. We may point out the desirability, therefore, that the new edition of the Pharmacopoeia, which is being prepared at present, require a sp. gr. of not less then 1.060."

• Pharm. Archives, 4, p. 167.

+ Bericht, S. & Co., Oct., '89, p. 37.

Date.

Sp. Gr.

Yield, p. c

Eugenol, p. c.

Observer.

Remarks.

It does not become apparent from the abstracts whether the oils were
distilled by the investigators or not. According to van Hees
Arch. d. Pharm., 111, p. 19) oil No. 4 seems to have been recti-
fied.

Oil from Jobst & Co.

Amboina

66

Commercial oil from Bourbon cloves.

Dist. 8 lbs. of Bourbon cloves over direct fire until empyreumatic products formed, oil rectified.

do., 4 lbs. with salt, oil rect., residue in still had clove odor.

do., 4 lbs. with more salt, oil rectified.

4 lbs. mixed with water and dist. with steam, crude oil almost colorless and not rect.

lbs. do. with salt, oil evidently not rect.

2 lbs. dist. in a Beindorff apparatus, oil colorless.

All of these oils were prepared by passing steam through the mixture
of cloves and water. After the bulk of the water had passed over,
it was cohobated and the dist. of the cloves continued with steam
under a pressure of 3 atm.-Van Hees attributes the higher sp. gr.
of Jahn's oil to a greater age of the cloves used. It would seem,
however, that the more rapid dist. with steam under pressure was
responsible for the lower sp. gr. of v. Hees' oils. Comp. also E.
A. Scharling (1852) in Pharm. Journ., 11, p. 469.
Oil dist. by observer.

English.
Foreign.

Oil obtained from "Sch. & Co. of L.," finest, twice rect.

do., do.

"extra light.'

See original for change in method of dist. !

Own. dist. Announce change in sp. gr., but do not state what change

In 1893 we find the following statement: *

66

According to an innumerable series of observations, the sp. gr. of oil of cloves is 1.060—1.070 at 15°. To set the standard below 1.060, as is done by the Dutch (1.041-1.060) and the Japanese (1.04-1.06) pharmacopoeias, we do not regard as commendable, but would rather regard an oil of the sp. gr. 1.04-1.041 as decidedly suspicious. The distillate from clove stems likewise has a sp. gr. of 1.055-1.065, hence does not differ materially from clove oil from cloves."

After pointing out that the old method of distilling most of the oils in an almost identical manner is unscientific, Schimmel & Co.† in 1895 call attention to the fact that changes in the method of distillation of cloves have resulted in the production of an oil with lighter sp. gr. due to the presence of substances that were previously either destroyed or lost. In place of getting an oil with a sp. gr. 1.060-1.066, they now obtain an oil the sp. gr. of which is 1.050 to 1.055. "We find, therefore, that the sp. gr. of unadulterated oil of cloves may vary from 1.050 to 1.068 at 15°; also that a pure, normal oil, such as is contained in the cloves and such as the consumer unquestionably desires, has a sp. gr. of 1.050-1.056. variation either way in individual cases is not excluded.

A slight

"Inasmuch as the Pharmacopoeia prescribes a sp. gr. of 1.06, we supply druggists and apothecaries with a fractionated oil, the sp. gr. of which is above 1.06; perfumers and soap manufacturers, however, are supplied with a normal oil."

10) According to the Austrian Pharmacopoeia, it should be miscible with alcohol, according to the Ph. Fenn. it should be soluble in spirit of sp. gr. 0.894, according to the Ph. G. in 2 vol. of dilute spirit; the requirements of the Norwegian and Russian Pharmacopoeias are like those of the U. S. P.

G.-H.-K. (p. 514) state that it should be soluble in 2 parts of 70 per cent. alcohol, the test with 70 per cent. alcohol being regarded as more characteristic than with a less volume of stronger alcohol. When freshly distilled, oil of cloves is more readily soluble in alcohol than twenty-four hours after distillation and later, thus indicating a chemical change which takes place in the oil upon standing only a short time.

11) Eugenol, in alcoholic solution, appears to have a slightly acid reaction.* The presence of esters in the oil might also account for a slight acidity due to saponification and liberation of free acid (e. g., salicylic and acetic acids). (Comp. No. 2.)

12) The ready solubility of the oil in glacial acetic acid enables the detection of substances less soluble in glacial acetic acid or in a mixture of oil of cloves and the acid.

Ibidem, Oct. '93, p. 28.

+ Bericht S. & Co., Oct. '95, p. 29.
*Hager's Commentary, Vol. 3, p. 222.

13) Eugenol, the principal constituent of the oil, being a phenol, forms phenylates, the potassium and ammonium derivatives being sparingly soluble in the amount of water directed to be used for the test. According to Dünnenberger,* foreign substances may influence the solidification. 14) This test distinguishes eugenol from ordinary phenol and, therefore, enables the detection of carbolic acid in the oil.

15) The adulterants are insoluble or but sparingly soluble in a solution of clove oil in dilute alcohol.

16) This test would enable the detection of the presence of such heavy oils as oil of cinnamon. The principal constituent of this, the cinnamic aldehyde, readily oxidizes to cinnamic acid, which is soluble in hot water and the presence of which would be indicated by its acid reaction to litmus paper.

17) This test seems to call for no further comment.

At the request of the chair Mr. Schlotterbeck then presented the following two papers, reading them by title, giving a very brief abstract of the first, and submitting them for publication.

THE DEVELOPMENT AND STRUCTURE OF THE SEED OF STYLOPHORUM DIPHYLLUM.

BY J. O. SCHLOTTERBECK AND C. R. ECKLER.†

Stylophorum diphyllum is a perennial, herbaceous plant, growing about two feet high in low woods from West Pennsylvania to Tennessee and westward to Wisconsin and Missouri. The pinnately divided leaves vary in size, and many, particularly the lower ones, measure a foot or more in length. The uppermost are in pairs, subtending one or more slender oneflowered peduncles. The flowers are about 2' broad, having four yellow petals. The sepals, two in number, are hairy; corolla yellow. Style distinct, columnar; stigma 3-4 lobed. The pods are ovoid, bristly, 3-4 valved at the base; buds and pods nodding. Juice yellow.

The study was begun upon the ovules of young flower buds, the oldest of which were nearly ready to open. Fig. 1 represents a portion of the placenta torn from the ovary of one of the youngest buds at hand. The little ovules as seen in drawing are quite straight, though some are becoming slightly bent. They measured .11 mm. long by .09 mm. wide, and near the end of each could be seen a very indistinctly simple cellular

structure.

A longitudinal section of the ovary from a young flower bud is represented in Fig. 2. The ovules may be seen as they appear in front view, and three in profile attached to placenta. These ovules measured (according to the dotted line) .16 mm. long by .12 mm. wide. At this stage

* Commentar zur Ph. Helv., III, p. 260.

+ Part Holder of the Frederick Stearns & Co. Fellowship in Pharmacy. School of Pharmacy, University of Michigan.