SECriON IIT., 1900 [21] Trans. RS, C. 
Il.—An Apparatus for the Determination of the Melting Point of Fats. 
By Franx T. Suurt, M.A., F.C.S., F.LC., 
AND 
H. W. CHARLTON, B.A.Sc. 
(Read May 29, 1900.) 
In the course of an investigation recently undertaken to ascertain 
the effects of certain feeding stuffs upon the quality of the pork pro- 
duced, it became necessary to determine the melting point of a large 
number of samples of fat. Since the work would include some twelve 
hundred determinations, a method was desired that would be fairly rapid 
and at the same time give uniform and comparative results. 
The various methods cited by authors are all more or less unsatis- 
factory, as is acknowledged generally by chemists, and it is extremely 
doubtful whether any of them, save perhaps that which notes the tem- 
perature at which a particle of fat assumes the spheroidal condition in 
a fluid of like specific gravity, give the true melting point, This latter 
method is an extremely tedious determination, and its use, when a large 
number of samples is to be examined, quite impracticable. 
While it may be possible with unmixed glycerides to obtain fairly 
concordant readings by observing the disappearance of opacity in 
drawn-out glass tubes, such does not seem to be the case with mixed 
fats. Pork fat, it may be stated, consists in proportions that vary 
slightly, according to the part of the animal from which the sample is 
taken, of olein, palmitin, and stearin—the first, fluid; the two last, 
solid, at ordinary temperatures. 
At the outset we made a trial of methods involving (a) the coat- 
ing of the thermometer bulb with the fat, and (6) the melting of the 
fat in drawn-out glass tubes, both open and sealed, using in some cases 
air, and in others, water, as the medium for conveying the heat. With 
these tubes, bound toa thermometer, we observed the temperature at 
which the fat became transparent and also at which the small cylinder 
of fat rose in the tube, if water was the medium, and that at which the 
first drop fell, if air was the medium employed. After giving these 
plans an exhaustive trial, we came to the conclusion that they were not 
reliable, for it was impossible, even with most careful attention to de- 
tails to get duplicate readings nearer than one or two degrees Celsius. 
Our attention was next directed to the method of Christomanos, 
in which mercury is used as the medium to convey the heat to the fat 
