272 TRANSACTIONS OF THE ROYAL CANADIAN INSTITUTE _ [VOL. XI 
Ferro-Molybdenum is found to be of value as a constituent in the 
manufacture of large castings, gun barrels, in which it is prized for its 
resistance to corrosive gas action, armour plate, armour-piercing shells, 
car steel, and magnets. 
Equal parts of molybdenum and chromium introduced into steel 
are claimed to be more preferable for many of the above uses, especially 
self-hardening steel. Two to five per cent. of molybdenum and ten 
per cent. chromium with little or no carbon will make steel acid resisting 
to a great degree. Nickel steels alloyed with molybdenum are found 
to possess desirable qualities. The tensile strength of molybdenum wire 
is given at from 200,000 to 270,000 pounds per square inch, as com- 
pared to tungsten with 480,000 to 580,000 pounds per square inch. 
Molybdenum wire-wound electric furnaces have special claims made 
for them. A thermocouple which uses the metal has been described 
recently. The lower oxides of molybdenum are highly coloured. Their 
use is recorded in colouring leather, rubber and porcelain. A soluble 
variety is used as a substitute for indigo. 
In some form not disclosed, molybdenum is added as a preservative 
to certain smokeless powders. 
The principal use of molybdenum, however, is in the manufacture 
of special steels to which, particularly in conjunction with chromium, 
manganese, nickel, cobalt, tungsten and vanadium, it imparts many 
desirable properties. These steels are used for a large variety of pur- 
poses, such as for crank and shaft forgings, high pressure boiler plate, 
ordnance, armour-plate, armour-piercing projectiles, permanent mag- 
nets, wire, and self-hardening and high speed machine tools. In a 
general way, molybdenum acts like tungsten in steel, but it is more 
active, and less is needed to produce a given result. Absolute figures 
as to the relative effect of the two elements cannot be given, as the 
effects are not exactly similar. The effective ratio of molybdenum to 
tungsten seems to be between one to two and one to three. 
Metallic molybdenum is used in various electrical contact making 
and breaking devices, X-ray tubes and voltage rectifiers, and in the form 
of wire for filament supports in incandescent electrical lamps, for winding 
electric resistance furnaces, and in dentistry, as a molybdenum tungsten 
alloy. 
CANADIAN MOLYBDENUM PRODUCTS. 
The only molybdenum products manufactured at present in Canada 
are C.P. molybdic acid, C.P. ammonium molybdate, and ferro molyb- 
denum. The International Molybdenum Company manufacture all 
three of the above at their Orillia, Ontario, works, this Company being 
