278 TRANSACTIONS OF THE ROYAL CANADIAN INSTITUTE  [VOL. XI 
developed in the treatment of some of our Canadian ores and the Depart- 
ment in endeavouring to correct these weaknesses and to improve upon 
the general adaptability of the machine, have evolved a type of apparatus 
which has been found to work very satisfactorily under almost all 
conditions. 
While the Department were experimenting for a solution of the 
separation problem, the search for molybdenite deposits of economic 
value continued throughout the country. Old.deposits were re-opened 
and developed with more vigour than heretofore and many new dis- 
coveries were made, but it was not until the spring of 1916 that the 
industry as a whole was strengthened by the development of the “‘ Moss 
Mine”’ of the Canadian Wood Molybdenite Company, near Quyon, 
Pontiac County, Province of Quebec. The occurrence of a mineral 
resembling graphite had been known in this locality for many years, 
but it was not until January, 1916, that the identity of this mineral was 
definitely established as molybdenite. 
The Canadian miner of molybdenum ores while encouraged by the 
reported prices for the mineral during 1915 had no definite guarantee 
that his product when ready for market would be accepted by the 
Imperial authorities; and as the great majority of these miners were 
men of small means it was difficult for them to raise the necessary 
capital for development without such assurances or contracts from the 
Imperial authorities. In June of 1916, the Imperial Munitions Board 
at Ottawa announced that they were in a position to purchase a con- 
siderable tonnage of molybdenite concentrates in Canada to be delivered 
before June 30th, 1917. At this time the Laboratories of the Department 
of Mines at Ottawa possessed not only the best concentration equip- 
ment, but were also in possession of a staff that had considerable ex- 
perience with the problem of concentration. It was, therefore, natural 
that the Imperial Munitions Board should turn to the Department of 
Mines for assistance in the securing of a part of the tonnage of concen- 
trates above mentioned, and an arrangement was entered into between 
the Imperial Munitions Board and the Mines Branch of the Depart- 
ment of Mines whereby the latter became the millers and assayers for 
the Board in all matters pertaining to the supply of metallic ores and 
minerals. 
The Moss Mine of the Canadian Wood Molybdenite Company 
having at that time developed sufficiently to make shipments, an agree- 
ment was drawn up with that Company whereby they were to supply 
the Mines Branch of the Department of Mines with 100 tons of molyb- 
denite ore weekly, the concentrates produced therefrom being purchased 
by the Imperial Munitions Board. At the same time, the Mines Branch 
