Abbildungen der Seite
[merged small][merged small][ocr errors]

Aster the results afforded by these analyses, it is impossible to confound this acid with margaric acid, and particularly too, as its composition agrees with that of another acid described by Dumas and Stass, under the name of athalic acid, and which they obtained by acting upon athal with potash, at a temperature of from 390° to 410° F. The acid then which has just been described, and which was obtained from the saponification of spermaceti, is athalic acid.

The athal that Chevreul mentions as being the base of spermaceti, and related to it, as glycerine is to the other fats, was found to be of the same nature that he describes it to be.

Conclusion as regards the Composition of Spermaceti considered as a fat.-Before coming to this conclusion, a résumé will be made of the results that have been arrived at in the different steps of this investigation. As regards athal, or what is considered the base of spermaceti, nothing has been brought to light to change in any way the statements made concerning its nature. Oleic and margaric acids have been proved not to exist in spermaceti. From the saponification of spermaceti, prepared as it was for these experiments, a small quantity of a fluid acid was obtained, but for reasons before stated, considered as an impurity. The acid product arising from the saponification of spermaceti, was found to consist almost entirely of athalic acid.

From these facts spermaceti, considered as a fat (I make this qualification, as a little farther on it will be attempted to be shown that it is not properly speaking a fatty body), is composed of one acid and one base, the former being athalic acid, and the latter athal, and it is therefore an athalate of athal, consisting of

Atomic weight.
One atom anhydrous athalic acid. C32H3103, 249:18
One atom anhydrous athal.......... C.H230, 235:18

One atom spermaceti ......... C6H6404, 484:36
That this is no doubt the true composition of spermaceti, will be
seen by the results afforded by the analysis of this substance, pre-
pared by crystallizing it out of absolute alcohol.

Exp. 1. 0:306 gram. spermaceti burnt with the bioxide of copper, gave 7-8945 gram. carbonic acid, and 0.370 gram. water.

Exp. 2. 0.2385 gram. spermaceti burnt with the bioxide of copper, gave 0.691 gram. carbonic acid, and 0.282 gram. water.

Exp. 3. 0.408 gram. spermaceti burnt with the chromate of lead, gave 1.198 gram. carbonic acid, and 0:486 gram. water.

Exp. 4. 0:314 gram. spermaceti burnt with the bioxide of copper and oxygen, gave 0.913 gram. carbonic acid, and 0.370 gram. water.

Exp. 5. 0.212 gram. spermaceti burnt with the bioxide of copper and chlorate of potash, gave 0.625 gram. carbonic acid, and 0.252 gram. water.

Comparing the per centage of carbon, hydrogen, and oxygen, afforded by these experiments, with that given by the supposed

composition of spermaceti (C64H0.0), we have in 100 parts

[blocks in formation]

484:36 100.00 100.00 100.00 100.00 100.00 100.00 Distillation of Spermaceti. The products furnished by the distillation of spermaceti were examined some time since by Bussy and Lecam, but they appear to have fallen into the same error with regard to them as was committed in the analysis of spermaceti, for they stated that oleic and margaric acids were among the products.

To make a correct examination of the products of the distillation of spermaceti, it was necessary that the substance should be in the greatest state of purity, as the presence of the smallest quantity of tallow, sometimes used as a means of adulteration, would serve to lead one into error. The manner of purification here employed, was to dissolve the spermaceti in a mixture of two parts of alcohol of 820, and one part of ether, allowing it to crystallize out, and washing the crystals with boiling alcohol of .820.

If some of the spermaceti, purified as just mentioned, be placed in a small retort, and this last in mercury heated to its boiling point, the spermaceti will be found to distil over slowly, and in fact this appears to be the lowest temperature at which the distillation takes place-a temperature of about 600° Fab. The matter distilled no longer possesses the properties of spermaceti; its melting is at a temperature somewhat lower, and it has a strong acid reaction upon litmus paper, as well as a peculiar smell, which though is not at all that of acroleine.*

If the products afforded by the distillation be digested with water, and this water be examined, it will be found not to possess the slightest acid reaction, a fact of considerable importance, and one that has been mentioned in a former part of this article as an evidence of the non-existence of oleic acid in spermaceti, oleic acid or any of its compounds always furnishing by distillation sebacic acid, an acid soluble in water. The water, moreover, will be found to have taken up nothing, it having simply acquired a slight odour, resembling that of the mass with which it was digested.

The steps taken to ascertain the nature of the products, were the following. The mass obtained from the distillation was digested with a solution of potash for an hour or two, and to this, placed in a convenient vessel, was added ether, and the two agitated together,

• If tallow be heated until it distils, it will be found to possess an odour which irritates both the nostrils and eyes, and the substance to which this odour belongs is called acroleine, and is a product of the decomposition of the glycerine in the tallow. It has been found that all bodies that contain glycerine, when heated sufficiently high, give the same odour, and it has therefore become the test for the glycerine.

and then allowed to repose. The ether arose to the surface, containing in solution certain products; this was drawn off, and a fresh portion added, and the agitation repeated. This operation was carried on until nothing remained that was soluble in this menstruum,

The ether was evaporated, and a residue obtained, consisting of an oily fluid holding spermaceti in solution. The separation of the oil from the spermaceti was attended with considerable difficulty, but by the aid of pressure at a very low temperature, and careful distillation, a small quantity of the oil was obtained tolerably pure.

0.222 gram. of the oil, burnt with the bioxide of copper, gave 0.688 gram. carbonic acid, and 0.282 water, and this in 100 parts, gives Carbon .............

85-04 Hydrogen...


99.16 These numbers show it to be a carburetted hydrogen, composed of equal equivalents of carbon and hydrogen, and this, together with such of its physical properties as I was able to examine, led me to believe it to be ceten, the carburetted hydrogen already spoken of as the supposed base of athal. Considering this oil to be ceten, its composition is represented by

In 100 parts.


Atomic weight,
32 Carbon ......... 194:18
32 Hydrogen ...... 32:00


Found. 85-04 14:12

226:18 100.00 99.16 The solution which had been treated with ether, was now perfectly transparent, and contained potash in combination with the acid products resulting from the distillation. To this was added a solution of chloride of calcium, by which means an insoluble compound of the acids and lime was formed, and this being decomposed by hydrochloric acid, furnished the acids for examination.

Although it was evident from what had been before done that no oleic acid could be present, yet to prevent any doubt, I made a direct examination for this acid, by digesting a portion of the acid mass with water and oxide of lead, and then treating the lead salt thus formed with ether, which dissolved no portion of it. The portion of the acid product not digested with the oxide of lead was found to consist of a solid acid, mixed with a very small quantity of a fluid one, which I considered to be the same that has been before mentioned, as a probable impurity of spermaceti, and for the same reasons then stated, it was impossible to make any examination of it.

The solid acid, which was obtained pure by repeated crystallization out of alcohol, exhibited the same physical properties, as well as

chemical composition, as the acid obtained from the saponification of spermaceti, and which has been shown to be athalic acid.

0.2715 of the acid gave 0.739 gram. carbonic acid, and 0.306 gram. water, making in 100 parts

Hydrated athalic acid.


Hydrogen ......................

12:52 12:38 Oxygen ...........



100.00 100.00 0.8625 gram. of the silver salt, when burnt, gave 0·254 gram. silver, which indicates in 100 parts, 29:44 silver, 31•61 oxide of silver, and an atomic weight of .250.

0-481 gram. of the silver salt, burnt with the oxide of copper, gave 0.932 gram. carbonic acid, and 0.368 gram. water. The per centage afforded by this will serve to show the identity between it and athalic acid.

[blocks in formation]

lu the distillation of spermaceti there are other products found than those just mentioned; but they appear only towards the latter end of the process, and result from an elementary decomposition; they are water, carbonic acid, carbonic oxide, and gaseous carburetted hydrogen, carbon being left behind in the retort; and these products are very small in quantity, except when the vessel is very deep and the heat strong.

If proper care be taken, spermaceti can be distilled almost completely, there being left behind an exceedingly small black residue. A circumstance which facilitates this complete distillation is, having kept the spermaceti for some time at the temperature of about 550° to 600° Fah.

The results of the investigations upon the distillation are, first, that it is impossible to distil spermaceti without more or less of it undergoing decomposition; and secondly, that the products of this decomposition are ceten and athalic acid, which fact serves to substantiate the correctness of the formula already taken for spermaceti, thus

One atom ceten ...................... C 2,H 3,
One atom hydrated athalic acid... C3, H3,04

One atom of spermaceti ............ C., H.,0,

Nature of Spermaceti. From the foregoing researches, I feel somewhat prepared to speculate on the true pature of spermaceti, for although it may be difficult to arrive at any positive conclusion with regard to it, still we should not be deterred from forming a judgment upon probabilities.

For many reasons, spermaceti would appear not properly to belong to the class of fatty bodies, and consequently not composed of an acid and a base. The fats properly speaking are known to be composed of acids, more or less different in their nature, in combination with glycerine; and when Chevreul found athal, as in spermaceti, accompanied with an acid, he considered athal as the base in this case, as well as making it the great mark of distinction between spermaceti and the fats.

Before going on to state the reasous why spermaceti should not be considered a fat, it would be well to mention what I suppose to be its proper position among the organic bodies. Spermaceli ought properly to be classed with cholesterine and athal, although approaching nearer to the fats than either of these substances; and that both the athalic acid and athal resulting from the saponification, are simply products of decomposition, brought about by the action of an alkali, peither of them existing ready formed.

The first reason for so believing, is based upon the extreme difficulty with which spermaceti is saponified, it requiring to be digested for a number of days in a strong solution of potash or soda, or to be fused with the saine alkalies at a temperature of from 212° to 220° Fah., before this change takes place. Now from the experiments of Dumas and others, it will be seen that the action of hydrated potash upon organic substances, at a temperature more or less elevated, is to decompose them, by changing their molecular arrangement, and that among the products formed acids play the most conspicuous part; the atom of water in the alkali is often importaut in bringiug about this change, by furnishing oxygen, hydrogen gas being evolved; but the action of this water appears to be but a secondary thing, and its influence is only felt where oxygen does not exist in sufficient quantity in the substance acted upon by the alkali, to furnish the products that are found with the quantity that they exact.

The above would appear to apply exactly to the case in question. The spermaceti contains oxygen enough, which when combined with one half of its other elements, serves to give rise to an acid ; it is quite possible that the action of the alkali, although not sufficiently strong at the temperature of 212° Fah., to determine the elements of the spermaceti, to appropriate the atom of water in the alkali to its complete conversion into athalic acid (I say complete conversion into athalic acid, for it will be shown that the action of an alkali at a high temperature is to convert spermaceti entirely into athalic acid); still it is of sufficient energy to disturb its

« ZurückWeiter »