282 ESSAY ON DEW, &c. 



substances, and is equal to the greatest which I had ever 

 known to occur, between those of the atmosphere and of 

 swandown lying upon grass. I had this evening placed no 

 swandown upon grass. 



These experiments were not made till nearly the whole of 

 the present edition of my Essay was printed, and could not, 

 therefore, be mentioned in their proper place. 



