30 BULLETIN 330, U. S. DEPARTMENT OF AGRICULTURE. 
by milling plants employing mechanical power for operating the 
machinery. Mortars and pestles were enlarged, and screens, fans, 
polishing brushes, and hulling stones were introduced. In Louisiana 
small iron " plantation hullers " were used to scrape or scour off the 
hulls and the bran coats in a single operation. 
With two or three exceptions, the 55 modern rice mills of the 
United States in operation in 1911 were located in Louisiana, Texas, 
and Arkansas. Various complex machines clean and scour the rice 
and prepare it for the market. Screens and fans remove the foreign 
material from the rough rice, which is then hulled between large re- 
volving stones. Fans blow out the loose hulls and paddy machines 
separate the grain not hulled by the first treatment with the stones. 
Hullers. pearling cones, and brushes scour from the hulled grain the 
light-brown bran coat, which is separated in a powdery form through 
fine wire screens. In the trumbles the rice often receives a coating 
of glucose and talc approximating two-tenths of 1 per cent of the 
former and one-tenth of 1 per cent of the latter. The coating mate- 
rials and the friction in the trumbles produces a bright luster. Grad- 
ing the milled rice according to the size of particles is effected by 
shaker frames fitted with screens having perforations of various 
sizes ; by reels, the sections of which are covered with wire of differ- 
ent sizes; and by cockle cylinders, which in revolving pick up the 
broken pieces in depressions in their inner surfaces and deposit them 
upon an inclosed apron suspended from the stationary axle. The 
various grades are bagged separately in pockets of 100 pounds each. 
Excessive breakage occurs when rice of the Honduras type is milled 
in a " plantation huller," and the finished product may have less than 
10 per cent of whole grains. The Honduras type of rice milled in 
a modern plant is broken to a considerable extent during the scouring 
process, which reduces its whole-grain content from 75 per cent as it 
leaves the paddy machine to 50 per cent as it leaves the brush. The 
Japan type of rice, on account of its shape, is broken to a less extent, 
and under similar conditions averages 92 per cent and 80 per cent, 
respectively, of whole grains. 
Approximately 10 per cent of the weight of the rice kernels of both 
Honduras and Japan types is removed by the scouring off of bran 
coat and germ. In other words, the average weight per thousand 
kernels of rice of the Honduras type is reduced from 21.1 to 22.8 
grams by the action of the hullers and pearling cone, and then to 22.1 
grams by the brush. The hullers and pearling cone reduce the weight 
of the grain of Japan rice from 22.1 to 21.5, and the brush further re- 
duces the weight to 20.2 grams. 
Chemical analyses show that the old mortar-and-pestle mills re- 
moved a somewhat smaller proportion of ash, ether extract, and crude 
