1 04 c fke Principles of Part III. 



Cor. 3. Hard water appears to afford a 

 ftrong nourishment for plants. This is 

 very oppofite to the common received 

 opinion : for gardeners never ufe it, when 

 they can get foft water > and if they fufpect 

 any hardnefs, endeavour to foften it as much 

 as they can, by letting it ftand expofed for 

 fome time to the heat of the fun. In this, 

 however, they are miftaken. This expo- 

 fition may make water harder j but can 

 never foften water which is confiderably 

 hard. The hardnefs of this water which 

 I ufed, and indeed of all hard waters * 

 which I have met with, was difcovered, 

 by experiments, to be owing to the acid of 

 nitre, joined to an abforbent earthy bafe. 

 The bafe in this water was a calcarious 

 earth $ in moft hard waters it is only an 

 abforbent. 



Cor. 4. Oil of olives, in the proportion 



* Vid, Experiments on bleaching, fe&. on hard 

 waters. 



Of 



