balloon. When exactly 94 pounds of cement have entered 
the bag, a scale automatically shuts off the flow. The 
bags are filled just as fast as the operator can slip them on 
and off the spout. 
UNIVERSAL CEMENT A LOW-PRICED 
COMMODITY 
About 114 tons of raw materials and 14 ton of coal 
(a total of 134 tons) are required to make a ton of cement. 
These materials must be assembled, dried, ground, pro- 
portioned, mixed, burned at 2800 degrees Fahrenheit to 
a hard clinker and then reground to an impalpable powder. 
In this finished state, the cement must be handled carefully 
to guard against moisture, packed in cloth or paper sacks 
or handled in bulk and loaded into cars with provisions 
for protection while being shipped. That nearly two tons 
of raw materials are required to pass through all these 
stages to obtain a ton of cement and that cement, including 
the cost of packing but excluding cost of the package itself, 
still sells F.O.B. cars at the mill for about $8.00 a ton, is 
another measure of the contribution that science has made 
to industrial progress. 
COMPARISON OF CEMENT PRICES 
There are two factors entering into the price the dealer 
or user pays for cement: Price at the mill and transportation 
charges from mill to point of use. The latter forms a 
relatively large part of the total price and obviously it is 
improper to compare a mill price at one time with a destina- 
tion price at another time; it is improper to compare a 
price on cement delivered at destination by railroad with 
a price on cement delivered by truck at site of work; it is 
improper to compare a price which includes a charge for 
the container—usually a cloth sack, the cost of which is 
refunded when the sack is returned in good or repairable 
condition—with a price which does not include a charge 
for the package. To avoid this and to arrive at the true 
relation of cement prices on different dates, prices at the 
mill exclusive of charge for package are the only fair basis 
for comparison.