4 BULLETIN 215, U. S. DEPARTMENT OF AGEICULTUEE. 
supply the local demand. While the southern corn is used as far as 
it goes, and is usually preferred, the larger part of the meal is either 
ground by southern mills from western corn or is milled in the 
North, usually in or near the region where the corn is grown. 
THE STONE PROCESS. 
With few exceptions the southern mills grind the corn by stones. 
The chief difference between the process of the small country mill 
with a single "run of stone," which grinds the grist that the farmer 
brings in on his back, and that of the large mill, with several to 40 
or 50 "run of stone," is in the perfection of the grain-cleaning and 
the bolting systems. In many of the mills native stones, notably 
the so-called Esopus stones from New York quarries, are preferred to 
French buhrs for the reason that they produce a soft, smooth meal, 
which is highly esteemed by southern cooks. 
The term "water meal" has been applied hidiscrimhiately to old- 
fashioned, stone-ground meal regardless of the fact that at the pres- 
ent time steam or even electricity is often the motive power. Natu- 
rally the nature of the milling machinery and not the power deter- 
mines the character of the meal. Stone-ground meal is either milled 
from corn without bolting, and consequently does not differ in com- 
position from the whole grain, except for the removal of a small 
amount of chaff by a simple fan device, or is bolted to remove the 
coarse bran and germ. It is stated that when unbolted meal is 
used the cook is accustomed to put it through a sifter, thus removing 
the greater part of the coarse, branny tissues, so that the final result 
attained is the same as if bolted meal had been used. Stone-ground 
meal, owing to the incomplete removal of the fatty matter of the 
germ, is characterized by its rich oily flavor, the taste for which when 
once acquired is not satisfied by degerminated meal in which the fat 
content is reduced to the minimum. 
In the small stone mills no attempt is made to dry either the corn 
or the meal, although it is well known that the corn must be moder- 
ately dry in order to prevent gumming in the mill and to insure 
keeping for a reasonable length of time. The friction of grinding, 
especially when the stones are set for producing a very fine, soft meal, 
develops considerable heat, which serves to drive off much of the 
moisture. In certain of the large mills drying apparatus is used to 
some extent for removing the excess of moisture from either the 
corn or the meal. In many of the mills, however, dependence is 
placed on the heat developed during grinding as well as on the expo- 
sure of the hot meal to the air in open conveyors. 
THE ROLLER PROCESS. 
In northern mills rolls have largely replaced stones, the process 
being one of gradual reduction similar to that employed in wheat 
milling. Prehminary to grinding, the corn is put through the 
