Two ounces of spermaceti was fused with one half its weight of powdered potash, care being taken that the temperature did not rise about 230° Falı.; the mass soon became solid, it was then allowed to cool, and afterwards treated with boiling water, which dissolved that portion of it which consisted of the acids, arising from the saponification incombination with potash; the other portion, consisting of athal and undecomposed spermaceti, was held in suspension. To the fused mass, treated as just mentioned, with boiling water, was added hydrochloric acid, which decomposed the soap in solution and liberated the acid which it contained, and this acid being fusible at a temperature much below that of boiling water, melted and arose to the surface along with the athal and undecomposed spermaceti. This mixture upon cooling was again fused with pulverised potash, for the purpose of acting upon that part of the spermaceti which was not yet decomposed. After this second fusion it was again dissolved in hot water, which solution, holding athal in suspension, was treated with a solution of chloride of calcium, and by double decomposition a combination of the acids resulting from the saponification of spermaceti and lime was obtained, which though was mixed with athal.

The water was filtered away from the mixture of the lime salt and athal, and the mass being dried, was treated with warm alcohol of 820, which dissolved the athal, and by repeatedly washing the lime salt upon a filter with warm alcohol, and lastly with ether, until the liquid that passed through gave upon evaporation no residue, it was obtained perfectly free from athal. By this process a small portion of the lime salt is dissolved, which can subsequently be obtained by treating the athal, from which the alcohol has been evaporated, with ether, which leaves undissolved the lime salt, and this is added to what remains upon the filter.

The lime salt was dried, and decomposed by dilute hydrochloric acid, which furnished me with the acids arising from the saponification, and like most of the fat acids, it floats about the water in flakes, which melt and collect at the surface, if the water be heated.

Having now the acids free from undecomposed spermaceti and athal, the first part of the examination, that is to say, the examination for oleic acid, was carried on as follows:

Examination for oleic acid in spermaceti.—A portion of the acid was digested with water and the protoxide of lead, at a temperature of 212° Fal., and in the course of a short time a lead salt was formed, which after being perfectly dried, was treated with cold ether, that dissolved no portion of the salt, a circumstance that could not have occurred, had the oleate of lead been present, as this salt is soluble in ether, and it is one of the means used to separate oleic acid from other fatty acids.

The above is the most direct way that we have of deciding upon the presence of oleic ocid, and the indication which it affords in the present case, was of too positive a character, to admit for a moment the existence of this acid in the substance examined. But this

single evidence, although sufficient of itself, has other indirect proofs to support it.

Redenbacker,* in his examination of the products of the distillation of oleic acid, observed the fact, that if this acid, or any substance containing it, be distilled, that sebacic acid is invariably formed. To this test spermaceti has been subjected by both Redenbacker and myself, with similar results; that is to say, that in the products afforded by the distillation of spermaceti, no trace of sebacic acid is to be found.

The products furnished by the oxidation of spermaceti by nitric acid, is another proof of the non-existence of oleic acid in this substance. Laurent, and subsequently Bromeis, have shown that when oleic acid is oxidized by nitric acid, that suberic acid is one of the most abundant products of this decomposition. Now, if spermaceti be oxidized by nitric acid no trace of suberic acid is furnished.

Having then the support of both direct and indirect evidence, I do not hesitate to affirm that spermaceti contains no oleic acid.

A question necessarily arising from this fact was, what was the acid that Chevreul had taken for oleic acid? To decide this the following steps were taken. That portion of the acid obtained from the lime salt, which had not been digested with the oxide of lead, was treated with carbonate of soda, this forming a soda salt, which being dissolved in hot water, was decomposed by tartaric acid. The fat acid, thus liberated from the soda, was dissolved in warm alcohol, and upon allowing the solution to cool, a considerable quantity of the acid crystallized out. The alcohol was poured off of this crystalline deposit, and concentrated by evaporation, from which another portion of the acid was allowed to crystallize. The alcohol was decanted a second time, concentrated and allowed to cool; and by repeating this four or five times, and at last evaporating all the alcohol away, there was left a small quantity of a solid fatty mass, which evidently still contained a considerable portion of the same acid that had been crystallized from the alcoholic solution. This acid had a melting point of 68° F., and consisted of a mixture of a fluid and solid acid, but it was impossible to obtain the former, in a state of purity; and as consequently no accurate examination of it could be made, none was undertaken.

The fluid acid that composed a portion of this mass, was in too inconsiderable a quantity, to be considered an essential constituent of spermaceti, particularly too as its presence is plausibly accounted for.

Spermaceti, as it exists in nature, is mixed with an oil, from which it is separated by pressure for domestic use; now it is impossible that by simple pressure we should be able to deprive the spermaceti completely of this oil, but in Chevreul's analysis, as well as in mine, the spermaceti of commerce was treated with hot alcohol of 820; still there are many reasons for supposing that even by this

• Redenbacker, properly speaking, was the first to generalize this fact, for it has been a long while since it was observed.

means it is impossible to extract all the oil; either from the fact that the oil is not more soluble in alcohol than the spermaceti, or that the attraction which the oil and spermaceti have for one another is too strong to be overcome by this means. Of the truth of this latter supposition we have many similar examples, particularly among the fats, a circumstance which renders their examination to the present day incomplete and imperfect. At some future time my attention will be directed to the examination of spermaceti prepared in a different manner from that pursued in the present case, particularly with the object of ascertaining whether spermaceti cannot be so purified as that its saponification will give rise to no fluid acid.

Thus, then, as regards the existence of a fluid acid in spermaceti, all that can be said is, that from the small quantity found, and from other reasons just stated, there are strong reasons for believing that it contains none, and that what has been found is due to an impurity which is not removed by alcohol of 820.

Solid Acid resulting from the Saponification of Spermaceti.I come now to the second part of the examination, and by far the most interesting; that of the solid acid obtained from the saponification of spermaceti, for it is this and athal that are the essential products resulting from the action of potash upon spermaceti.

The solid acid obtained in that part of the examination which was directed to ascertaining the presence of a fluid acid in spermaceti, and which was crystallized out of alcohol, was found to be nearly in a state of purity. This was dissolved in a mixture of equal parts of alcohol and ether, and allowed to crystallize out. This operation was repeated two or three times, and the crystalline deposit was then thrown upon a filter and washed with cold alcohol of 820. The acid thus obtained was pure, and possessed the following properties.

It melted at 130° Fah., and upon cooling crystallized in small needles, diverging from a number of centres, and when cool is white; it resembles somewhat in appearance wax, it being slightly translucent. It was dissolved in all proportions by alcohol of 820, at 140° Fah., and upon cooling crystallized out in small needles, which collected together in the form of moss, and sometimes in that of cauliflower; from this, the alcohol can be poured so as to leave it almost perfectly dry. Out of ether this acid crystallized with difficulty, owing to its excessive solubility in this menstruum. When heated to a high degree, it volatilizes without leaving a residue. The alcoholic solution reddens litmus.

The physical properties of this acid will be seen to differ from those of margaric acid, which it has been supposed to be, but there is no striking difference between these two bodies in composition, as will be seen in the results afforded by the analysis of this body.

Exp. 1. 0.2815 grammes of the acid burnt with the bioxide of copper gave* 0·7725 gram, carbonic acid, and 0-320 gram. water.

• All my calculations are made with the atomic weight of carbon given by Liebig and Redenbacker (75.85 oxygen, being considered 100, or 6·068 hydrogen being taken as unity).

C

Exp. 2. 0-2325 gram. of the acid burnt with the bioxide of copper gave 0.637 gram. carbonic acid, and 0-261 gram. water.

Exp. 3. 0.328 gram, of the acid burnt with the chromate of lead gave 0.890 gram. carbonic acid, and 0·3685 gram. water.

These three analyses furnish the following proportions of carbon, hydrogen, and oxygen, in 100 parts of the acid:

Having thus found the relative proportions of the elements contained in this acid, it was necessary to examine one of its salts, to ascertain its atomic composition, and for this purpose, as in most cases, its combination with the oxide of silver was chosen, but to form this salt it was necessary first to form its soda salt.

Soda Salt.-A portion of the acid was digested with a solution of carbonate of soda, until a complete combination had taken place, which is easily known by the acid no longer floating on its surface, it having all united with the soda, forming a salt soluble in water. The solution of this salt, which contained an excess of carbonate of soda, was evaporated to dryness in a water bath, and the dry mass, pulverised, was treated with absolute alcohol, which dissolved the soda salt and not the carbonate of soda; from this the alcoholic solution was separated by filtration, and this last, evaporated to dryness, furnished the salt perfectly pure.

Silver Salt. This salt was formed by a double decomposition of the salt just described and nitrate of silver. The soda was dissolved in water, and to this was added a solution of nitrate of silver, which produced a white flocculent precipitate, the salt in question. This precipitate was thrown on a filter, and well washed with warm distilled water, and dried at 212° in the dark.

This silver salt, when burnt in a porcelain crucible, gave the following results:

Out of these the following per centage of silver and oxide of silver

From the same analyses the atomic weight of the anhydrous a id was calculated to be, from

Exp. 1. 250.00

66 2. 250.52

Mean

66 3. 249-36

250.24

The silver salt was now analyzed with bioxide of copper. to ascertain the quantity of carbon and hydrogen that it contained. 1. 0.4735 gram. silver salt burnt with the bioxide of copper, gave 0.910 gram. carbonic acid, and 0.3595 gram. water.

2. 0-483 gram. silver salt burnt with the bioxide of copper, gave 0.934 gram. carbonic acid and 0.3705 gram. water.

From these analyses we find in 100 parts of the salt

1.

2.

Mean.

The atomic weight of this acid, found by burning the silver salt, was 250-24. The acid not in combination with a base, contains one atom of water, and has for its composition

Atoms.

In 100 parts.

75.13