has been repeated several times,
the sirup is finally changed to a yellowish-gray mass. This is now brought
into a large mortar, and rubbed up under a mixture of alcohol and ether.
After some time the whole mass is transformed into a gray powder. It is
quickly filtered off with the aid of an aspirator, washed with alcohol and
then with ether, and brought under a desiccator with concentrated
sulphuric acid. In order to purify the substance, it is dissolved in water
and treated with bone-black. The solution is then evaporated to a sirup,
and this poured into a mixture of equal parts of anhydrous alcohol and
ether. In this way the new compound is obtained as a very fine, pure white
powder which rapidly settles. It has much the appearance of starch. Under
the microscope it is perfectly amorphous. In the air it deliquesces much
more rapidly than ignited calcium chloride.
Treated with dilute mineral acids or oxalic acid on the water-bath
gallisin is transformed into dextrose. It does not ferment when treated in
water solution with fresh yeast. The analyses led to the formula
C_{12}H_{24}O_{10}. When treated under pressure with three times its
weight of acetic anhydride at 130-140 deg. it dissolves perfectly. From the
solution a product was separated which on analysis gave results agreeing
with the formula C_{12}H_{18}O_{10}(C_{2}H_{3}O)_{6}. The substance
appears therefore to be hexacetylgallisin.
Physiological experiments on lower animals and human beings demonstrated
clearly that gallisin has neither directly nor indirectly any injurious
effect on the health.--_Berichte der Deutschen Chemischen Gesellschaft,
17, 1000; Amer. Chem. Jour._
* * * * *
THE COMBINING WEIGHTS, VOLUMES, AND SPECIFIC GRAVITIES OF ELEMENTS AND
COMPOUNDS.
Under the title of "Figures Worth Studying," Mr. William Farmer, of New
York, read a paper before a recent meeting of the Society of Gas Lighting,
from which the _American Gas Light Journal_ gives the following:
I have prepared the following table, which contains some of the elements
and compounds, with their combining weights, volumes, and specific
gravities. When the combining weight of any of these elements and
compounds is taken in pounds, then the gas or vapor therefrom will always
occupy about 377.07 cubic feet of space, at 60 deg. Fahr. and 30 inches
barometer. If we divide this constant 377.07 by the combining weight of
any of the substances,
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