98 *, FIRESIDE SCIENCE. 



profitable to manufacture. The refiner does not 

 care so much about the color of the sugar he buys 

 as he does about the distinctness of crystalline struct- 

 ure. The color he can remove ; but if a large por- 

 tion of the sugar is composed of molasses or uncrys- 

 tallizable sugar, he is subjected to loss. Consum- 

 ers of dark, coarse sugars are not generally aware 

 of the fact that, beside the other impurities, they 

 contain large numbers of a most disgusting insect 

 the Acarus sacchari. This insect is a very near 

 relative of the Acarus scabiei, which produces the 

 uncleanly and unpopular affection called the " itch." 

 Indeed, the sugar insect often produces upon the 

 hands and arms of grocers pustular eruptions, re- 

 sembling true psora, or scabies. These insects bur- 

 row beneath the skin, and deposit their eggs, creat- 

 ing much irritation and an intolerable itching. The 

 number of acari found in raw sugar is sometimes 

 exceedingly great, and in no instance is the article 

 entirely free from either the insects or their ova. 

 Dr. Hassall examined one specimen, in which he 

 estimated that no less than one hundred thousand 

 existed in every pound of the sugar. In ten grains' 

 weight he counted five hundred, many of which 

 were so large as to be seen by the naked eye. He 

 observes, that " it is inconceivable that thousands 

 of these creatures can be introduced into the human 

 stomach without serious endangerment to health ; " 



