INSECT POWDER. 11 



Arriving at the mill the flowers (which have l)een thoroughly dried) are fed to a set 

 of burr millstones, just as wheat is handled in making flour by the old process. The 

 grist is carried by an elevator to a sei)arator which, by proper sieves, separates the 

 coarser particles of the grist, allowing only the finest, dustlike powder to pass through. 

 This powder is carried Ijy an elevator to an adjoining building, where it is put up in 

 tin cans for the market, while the coarser particles thrown off }>y the separator are 

 returned to the millstones. 



The flowers become heated while being reduced to powder, but the latter, in pass- 

 ing through a large series of elevators, loses its heat to a great degree before it is 

 put into the cans for the market. 



Slaus-Kantschieder (261), in 1913, described the preparation of 

 insect powder in Dalmatia as follows: 



The flowers are prepared as powder in Dalmatia, as well as in Trieste. The largest 

 Dalmatian mills, located in Sebanico, are driven with electrical power from "Krka- 

 fallen." Further, several smaller concerns in Zara, Ragusa, and upon the islands of 

 " Mittel-Dalmatiens " carry on the grinding of the flowers. In Trieste the grinding of 

 the chrysanthemum plants is carried on in al^out 10 mills, and this is the place where 

 most of the adulteration occurs. 



In the United States, in addition to Stockton, Calif., where Buhach 

 is manufactured, insect flowers are ground on a large scale in Balti- 

 more, Peoria, and New York, and to a smaller extent in Philadelphia, 

 St. Louis, and other places. In most cases the older firms still use 

 stone "chaser" mills, while the newer firms employ steel disc mills. 



A *' chaser" mill consists simply of a pair of millstones joined by a 

 horizontal axis which is connected with a vertical shaft. By means of 

 power the shaft is turned, and the two stones roll around, one after the 

 other, on a heavy block of granite. These millstones, which are also 

 of granite, are about 2^ feet in diameter by 8 inches thick, and weigh 

 several hundred pounds each. Flowers imported into this country- 

 are received in bales done up in burlap, containing on an average 

 about 440 pounds net each. The contents of the bales are emptied on 

 the floor, and any large stones, which are sometimes added to give 

 weight, removed. The flowers are then shoveled or dumped into the 

 box which surrounds one of these stone chaser mills, where they are 

 kept in the path of the revolving stones, which are mounted about 2 

 feet apart, by means of a revolving arm. The flowers are soon reduced 

 to a fine dustlike powder which in some mills is periodically shoveled 

 out, and in others is removed from pockets in the sides of the inclosing 

 box. The powder is so fine that it is carried up by the air currents 

 produced by the revolving stones, and settles into pockets provided 

 for that purpose. The top, as well as the sides of the mill, is boxed in 

 very tightly to keep the powder from flying everywhere. After grind- 

 ing, the powder is put through a sieve or bolted, and the tailings re- 

 ground. In some cases a sieve of only 40 meshes to the inch is used, 

 whereas other firms employ 110-mesh bolting cloth. 



The steel disc mill, used by some firms in grinding insect flowers, 

 consists of a series of perforated steel discs with lugs on the edge which 



