504 
PHILOSOPHICAL SOCIETY OP WASHINGTON. 
viz., 1, aluminium bronze, a 10 per cent, alloy of aluminium and copper; 
2 , tiers argent, a 66f per cent, alloy of aluminium and silver, and, 3, the 
“ mitis ” casting, an alloy of cast iron with a minute proportion of alu¬ 
minium (aV of one per cent.) to improve fluidity in the mold and solidity 
in the Casting. The Cowles incandescent electrical furnace for the smelt¬ 
ing of refractory ores, including those of aluminium, was described from 
the patents; also the electrical furnace of Bradley and Crocker for the 
procurement of sodium. The sodium process of Frishmuth of Philadel¬ 
phia for obtaining aluminium was also described from the patents. Speci¬ 
mens of pure aluminium and aluminium bronze were shown. 
Sodium.—Its uses in metallurgy were referred to and the mode of its 
production on a commercial scale indicated. 
Potassium.—An industrial use in the manufacture of fuses to ignite and 
burn on contact with water was described. 
Magnesium.—Several modes of utilizing this metal in the production of 
artificial actinic light for instantaneous photography were described. 
Cadmium.—The use of this metal as a component of fusible alloys for 
dental and other purposes was described and its use for the preparation 
of artist’s colors referred to. 
Iridium.—The mode of utilizing this metal in the arts by melting and 
casting it as a phosphide was described. Its principal industrial uses are, 
for tubular points in fountain pens, as a hard facing for burnishers, etc., 
as draw-plates for wire drawing, and as indestructible bearings for fine 
machinery in lieu of jewels, for which its great hardness and unchange¬ 
ableness recommend it. As a phosphide, it is also useful for anodes in the 
electro-deposition of iridium. A specimen of the electro-deposited metal 
was shown. 
Palladium.—This metal finds a valuable use in the hairsprings, compen¬ 
sation balances, and other quick-moving parts of watches to be used near 
dynamo-electro generators, where ordinary watches with steel balances 
are rendered useless by magnetic influences. Palladium is recommended 
for these purposes by its unchangeableness, elasticity, and low coefficient 
of expansion. 
Strontium.—The industrial uses of this metal arise out of the magnifi¬ 
cent crimson light of its spectrum, which qualifies it for coloring rocket 
signals for military and naval purposes. 
Tungsten.—This metal has recently been found valuable for military 
projectiles on account of its high specific gravity conjoined with sufficient 
hardness, giving it superiority over either lead or steel, neither of which 
unites these two qualities. Specimens of such proposed projectiles were 
exhibited, 
Yttrium, Lanthanum, Zirconium, and Thorium.—The great refractory 
qualities of the oxides of these metals qualify them for incandescents in 
gas-lighting with non-carburetted gas, a novel way of utilizing them hav¬ 
ing recently been introduced and patented in Europe by saturating web¬ 
like cylinders of textile fabric with aqueous solutions of the salts of said 
