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proved to me that this acid is a constant product of this oxidation. The liquid 
which passes over after having been saturated with caustic potash yields a white 
precipitate with nitrate of silver, which, on heating, turns brownish or blackish, 
probably from some formic acid. The salt of silver, being decomposed by sul¬ 
phuretted hydrogen, yields a few large crystals of a third acid, the nature of 
which I have not been able yet to ascertain. It would be rather difficult to 
explain how it could happen that fumaric acid , for instance, passed over. The 
upper part of the retort itself showed inside numerous small acicular crystals, 
which were readily dissolved by water, and were recognized as oxalic acid , 
which, however, is not found in any considerable proportion, or probably is 
partly destroyed by long contact with nitric acid. In another essay I was not 
able to find any trace of it. 
The contents of the retort at last were a thick colourless liquid smelling but 
very little of butyric acid ; water quickly dissolved it, leaving only a few oily 
drops, which, on addition of a large quantity of water, almost entirely dis¬ 
appeared ; they may perhaps have been valerianic acid. 
The aqueous solution, after due concentration, yielded hard crystals, which 
on careful examination, showed all the reactions of succinic acid. Exactly 
neutralized with ammonia, their solution produced an abundant reddish-brown 
precipitate in a solution of perchloride of iron, a white one in neutral acetate 
of lead, which was dissolved by the acetate in excess. Chloride of calcium is 
not precipitated unless alcohol is added ; the succinate of lime dissolves quickly 
in a solution of chloride of ammonium, but is again precipitated by a large 
volume of alcohol. I have no doubt that, with the opportunity of treating 
more considerable quantities of the stearoptene, several other acids of the series 
of the fatty acids, or others of the same class as those formed by the reaction of 
nitric acid on waxes and fats (suberic acid, pimelic acid, etc.) would be met with. 
Succinic acid , however , is by far the chief product of the oxidation of rose- 
stearoptene ; yet from wax and fatty bodies it differs by its composition. Now, 
there is another hydrocarbon, or, rather, a whole series of hydrocarbons, com¬ 
monly called paraffin, bearing a very close resemblance to the stearoptene under 
examination. By the researches of Ilofstadter* we are informed that succinic, 
valerianic, and butyric acids are formed, when, if paraffin of different extrac¬ 
tion is boiled with fuming nitric acid ; of the first-named acid, 18 per cent, may 
be obtained. Neither potassium nor caustic potash act on paraffin. I have re¬ 
peated Hofstadter’s experiments, and have succeeded well in obtaining the acids 
in question. Faraffin is even much easier oxidized by nitric acid than rose- 
stearoptene, but the latter yields much more succinic acid. The fusing-point 
of the different paraffins is generally about 107° F. (42° C.))to 140° F.(60° C.) ; 
yet one sort from France (Autun), prepared and examined by Laurent,f 
melts at 26 4° F. (33° C.) exactly like our stearoptene of the rose. 
The chemical position of the various bodies called paraffin, azokerit, etc. is not 
yet settled. We do not know whether their composition agrees better with the 
general formula C n H re , or with C„H w+2 ; probably they form a whole series 
of very analogous bodies, the separation of which has not yet been thoroughly 
realized. I hope to be entitled, in conclusion, to say that it is probable, when 
all these hydrocarbons are fully known, the stearoptene of roses will be found 
to belong to the paraffin series. 
I have not, as yet, had the opportunity of procuring Turkish rose-oil of un¬ 
questionable purity, but there can be little doubt that its stearoptene is of the 
same nature as that of the English roses, the examination of which I have here 
detailed. 
* Annalen der Chemie und Pharm., 94 (1854), p. 333. 
f ‘ Annales de Chimie et de Physique,’ 54 (1833), p. 394. 
