40 
W. C. EBAUGH 
d. Iron blast furnaces. Gases from iron blast furnaces must 
be cleaned before they can be used in gas engines. The Cottrell 
process mentioned above has proved its value in this service, 
and the ores of certain districts, Alabama in particular, contain 
such quantities of potash that recovery of this material becomes 
of great economic importance. Only 200 tons of potash were 
made from these sources in 1917 — all of which came from ex- 
perimental plants — ^but largely increased yields are expected in 
1919. 
R. K. Meade has estimated that an expenditure of $37,000,000 
for potash recovery plants at iron and cement plants throughout 
the country would add 200,000 tons of by-product potash, or 80 
per cent of our pre-war consumption, to America’s output. This 
would be a low price to pay for economic independence in this 
line, and the amount involved seems small indeed when com- 
pared with war-time ^ ^drives” for $30,000,000 for Armenian and 
Syrian Relief, $170,000,000 for a United War Work Campaign, 
$200,000,000 for a Red Cross Fund or a $6,000,000,000 Fourth 
Liberty Loan! And the irony of fate is again evident. 
America’s chemists and engineers have shown how to wrest Ger- 
many’s “one economic weapon” from her hands by recovering 
and utilizing nuisance-creating material that is now allowed to 
go to waste on an enormous scale, by industries well established 
and easily able to provide necessary plants and technical skill. 
e. Manufacture from silicates. For decades it has been recog- 
nized that the logical source of potash is silicate minerals, and 
much effort has been expended on developing processes to ex- 
tract potash from feldspar, leucite (Wyomingite), glauconite or 
green sands, and similar material. Recently it has become 
general knowledge that tailings dumps often represent large 
quantities of locked-up potash; those at Cripple Qreek, Colorado, 
run 10 per cent in potash, and those from the Utah Copper Com- 
pany’s mills, at Garfield, Utah, carry more than 6 per cent of 
this constituent. Such tailings are already finely ground and 
constitute the most accessible source of raw material for a sili- 
cate potash industry. The Utah Copper mills alone, treating 
30,000 tons of ore daily, could supply enough raw material 
