324 ANNUAL REPORT 
position cannot now be corrected in the average plants of today, but must 
be allowed to pass on with the certainty of producing an inferior product. 
The bins, of whatever kind, should be supplied with bottoms per- 
mitting of emptying by gravity. This applies to the cement bins as well 
as the raw stock bins. 
In the accompanying diagram this equipment is outlined. It will 
be noted that the draft for the kiln is provided by exhaust fans, the waste 
heat being passed through boilers and a feed water heater. The heat of 
the cooling clinker is supposed to be used for preheating the air introduced 
for the combustion of the coal. If the clay is very coarse, or if sandstone is 
added to the mixture, it might be necessary to insert a tube mill between the 
clay disintegrator and the clay bins, in order to insure sufficient grinding 
or, 1f preferred, another tube-mill might be added to the fine grinding 
equipment and the feed reduced for each mill, so that more time is given 
for the grinding. A flue is also indicated through which some of the waste 
gases might be exhausted and conducted through the dryer, so that the 
fuel item for the drying is eliminated. The coal should be ground in 
a disintegrator and Griffin mills. This diagram, of course, is only in- 
tended as a suggestion, for covering the ordinary difficulties which arise. 
In any individual case, modifications would be likely to be needed to suit 
the special peculiarities of the stock and fuel. 
Wet Process. —Here the machinery required is much simpler ome. 
to the soft and fine grained character of the materials. 
Marl. Clay. 
1. Blunger or wet pan with i Dryer 
perforated bottom. 2. Disintegrator. 
2. Tank, kept agitated. @.  lexbat 
ae Mixer: : 
Tube-mills. eo 
c. Storage and correction tanks. 
de Kalns: 
e. Clinker cooler. 
f. Kent mill. 
e@. Wind separator. ei 
Ins (Gsemnonin saouiilll, 3 
Storing Cement.—The stock house should be large enough to hold 
at least one month’s run of cement. It is preferably built of concrete 
and divided into a number of bins. By testing the cement in each bin 
by the usual physical tests, taking care to sample the bin thoroughly, the 
