372 
( KMKNT MATERIALS AND INDUSTRY. 
[bull. 243. 
(New York Rosendale). The industry affords very fair profits, and th 
output in the United States is increasing steadily. 
American slag cements are certainly superior in strength, uni- 
formity, and rapidity of set to European slag cements. Slag cemen 
are not, however, Portland cements, and the sooner this fact is recog 
nized and publicly admitted by their manufacturers the better will be 
the prospects of the industry. For, though slag cements are entirel 
unfitted for many uses to which Portland cements ma} r be applied, 
there are certain uses for which they are well adapted, and if, for any 
particular use, a slag cement is as good as a Portland, its lower price 
will of necessity remote any danger of Portland competition. 
