98 A TRACT OF MISCELLANIES. 



tion of the insects at that place was in connection 

 with the cloth beneath. 



We therefore removed the cloth to some distance, 

 and immediately the swarm of insects changed their 

 place, and again t oo up their position as before 

 above the cloth. This we repeated several times, 

 and with the same result. 



163. There are certain classes of artisans, such as 

 flax-dressers, millers, hewers of stone, and others, 

 who, it is said, are particularly subject to chest-com- 

 plaints, arising, as it is supposed, from the gritty, 

 dusty or filamentous particles which they draw into 

 their lungs while engaged in their respective occupa- 

 tions. Thus the flax-dresser inspires the filamentous 

 particles which float so abundantly in the atmosphere 

 that surrounds him. The stone-hewer inhales the 

 gritty particles which are driven off into the atmo- 

 sphere while operating upon calcareous or siliceous 

 blocks of stone; and at one time, too, the flint-grinders, 

 who before the process of grinding under water was 

 adopted, were enveloped during their operations in 

 an atmosphere charged with minute siliceous parti- 

 cles. All those classes were particularly subject to 

 chest-complaints. Now, how is it that the people 

 of this country are so subject to pulmonary diseases ? 



