14 ON ADIPOCIRE, AND ITS FORMATION. 
longer, when a drusy crystalline deposit made its appearance. The following are the melt- 
ing points for these two precipitates : 
Precipitate in 1° . 5 melts 62° 63° : 4 solidifies 44° 5—40° 
Gs (rion . 5 «51° 50° é 6 “44° 5 —48° 
’ The fat deposited in 2° melted at 58°, and solidified at 52°, and the fat separated from 
the liquid of this bottle, melted at 59°5, solidified at 53°, but continued translucent down 
to 83°. After the above melting points, 1° and 5° were observed, the same fat was raised 
slowly to the melting points, and then kept for a considerable time in the thermostat, at 
100°, the points were again determined, and found to be the same. 
The liquids separated from the fats 1°—6°, gave the following results: 
The fat from Liquid 1° E : melts 86°—46° ' ‘ solidifies 41°—? 
“ “ 2° ; i « 39°—41° : ; 87° —852 5 
“ “ GIORS) : & §9°—62° 5 ‘ « 40° 5—35° 
« c By? : é “ 62°—66° : : « §8°—53° 
“ “ 6° : b “ 538°—56° ‘ f cc Ale? 
The melting point of liquid 2°, does not accord with that above stated, but I note the 
experiments as they were observed, merely mentioning that I observed carefully, and am 
not conscious of having made an error. The above points seem vague, but it was impos- 
sible to fix a point definitely, as a cloudiness persisted up to the highest degree stated, so 
I prefer to give the limits of certainty. In 1° and 6° the solidifying points, 41°, were 
taken when the liquid in the capillary tubes seemed to become solid, but it remained 
translucent for a long time below this point, and 6° only became opaque (and that gradu- 
ally) when suffered to stand in the air. 
We are reminded here of Duffy’s observations upon certain isomeric transformations of 
the fats, (Quar. Jour. Ch. Sec. V. 197.) He noticed that stearine heated 1° above its point 
of solidification, became transparent, but soon after resumed its opacity; and Heintz made 
a similar observation. Duffy attributes this to an isomeric transformation of the fat by 
the heat; but it seems to me simpler until an isomerism be more distinctly proven, to as- 
sume a mixture of fats, which unite to form a definite compound under the circumstances, 
and which has the above. mentioned property. Heintz’s researches on the fats should 
make us look with suspicion upon fats as pure, that are only purified by crystallization. 
* The liquid from No. 3 was all absorbed by the pressing cloths, and not collected. 
+ Since the above was written, I have received the Journal fiir Pract. Chemic., Heft IM. Band LXIU. in which 
some late results by Heintz on this point are communicated. He artificially prepared chemically pure stearine 
from the acid and glycerine, by Berthelot’s process, and found that it had two melting points, first at 55°, then 
solidifying and melting again when the heat reached 71° 6. 
