1866. | Physics. 435 
name of metallic phosphorus, which he subdivides into metallic 
crystallized and metallic amorphous. Commercial amorphous 
phosphorus is often in the crystalline state. 
Microscopists and others who are occasionally engaged in the 
examination of organic tissues and gelatinous substances, will be 
glad to know of a method by which these bodies can be dried without 
the application of heat. A large number of substances, like gum, 
&c., have, as is well known, the property of agglomerating, upon 
drying, into amorphous masses, more or less solid and translucent, by 
which, on the one hand, the original appearance of the freshly made 
preparation is lost, and, on the other, complete desiccation rendered 
very difficult. In order to obviate this adhesion of the elementary 
particles occurring during the drying of such substances under 
ordinary circumstances, Reischauer has proposed to carry on this 
operation out of contact with the atmosphere, and by the aid of a 
suitable ethereal medium. 
The apparatus employed for this purpose is, in its simplest form, 
a well-closed glass vessel filled with ether or a similar liquid, at the 
bottom of which is placed the chloride of calcium, quicklime, 
calcined sulphate of copper, &c., intended to absorb the water. A 
shallow vessel is placed below the surface of the liquid for the 
reception of the substance to be dried. The modus operandi is now 
avery simple one. ‘lhe ether continually yielding its water to the 
chloride of calcium constantly withdraws it in turn from the 
substance to be dried, until, finally, the latter corresponds in its 
hygroscopic state with that of the desiccating agent. The thorough 
wetting in this manner of the constituent particles of the substance 
to be dried (which, of course, must be insoluble in an ethereal 
liquid) prevents their sticking together, and the original appearance 
is retained when dry. 
Gum, separated by precipitating the aqueous solution with 
alcohol, gives an amorphous white mass of very slight adhesiveness, 
and with no trace of the common glass-like condition. The so- 
called diastase, or the body obtained by precipitating the extract of 
malt with alcohol, deprived of water under ether, forms spongy and 
very light granules. In this state it retains its effect upon starch. 
The microscopical examination of starch paste dried by this process 
leaves scarcely a doubt that the starch grains exist in paste in a 
state only of extraordinary expansion, and not in that of actual 
solution. Hops give a mass similar to diastase, but, however, no 
longer capable of producing fermentation. The organs of plants 
dry rapidly under this treatment, commonly retaining their colour, 
unless unusually delicate. Taken from the ether, they soon 
become moist again in the air, and rapidly lose their colour, which 
by a continuance in the liquid appears remarkably fine. 
The behaviour of animal productions under this method -of 
