154 ON THE CHEMICAL PROPERTIES OF SILK. 



" Clie virtues of cleansing the blood, making tl 

 spirits brisk, and the heart pleasant." 



It is said, that if a thin silk veil is worn ii 

 countries where malaria is generated, that it wil 

 have the effect of counteracting its noxious qua 

 lities. 



The water in which cocoons are immersed prepa- 

 ratory to reeling, acquires such a strong lathery 

 consistence, that air-bells may be made with it. 

 which are so flexible and strong that they have beer 

 known to remain without bursting for upwards ol 

 twenty-four hours. These bells exhibit the pris- 

 matic colours in as high a degree as those formed ol 



Count Rumford observed, that raw silk has i 

 remarkable power of producing pure air from water 

 He found that, by introducing thirty grains of thii 

 substance, first washed in water, into a thin glast 

 globe, four inches and a half in diameter, having 8 

 cylindrical neck three-fourths of an inch wide, and 

 twelve inches long, inverting the globe in a jai 

 filled with water, and exposing it to the action 

 the sun in the window ; in less than ten minute? 

 the silk became covered with an infinite number o: 

 air-bubbles, gradually increasing in size, till, at thi 

 end of two hours, the silk was buoyed up by tlu-ii 

 means to the top of the water. They separated 

 themselves by degrees, and formed a collection o: 



