4^o ESSAYS AND OBSERVATiaNrS 



Art. XIII. 



Of the various Strength of different Lime'* 

 ivaterSt h) Robert Whytt, M. D» 

 F. R, S. telloiv of the Royal College of 

 Pbyficims^ and Profjfor of Medicine in th^ 

 Univeifitj of Edinburgh. 



■^jT" HE Reverend and ingenious Dr Ste- 

 ^ phen- Hales, having informed me, 

 in a letter dated May 1751, that he had 

 found the ftrength of lime-water much 

 increafed, by pouring it a fecond time oa 

 quick-lime, frefli from the fire ; I thought 

 it might be worth while to make a few 

 experiments, in order to determine, with 

 fome degree of certainty, the different 

 ftrength of different lime-waters : From 

 rhefe experiments, it appeared, that lime- 

 water acquired a eonfidcrable addition of 

 ftrength by being poured on quick^lime 

 newly taken from the fire ; and that the 

 firft water got off quick-lime was fen- 

 fibly ftronger than the fourth and fuc- 



ceeding ones *. 



On 



• ElTay 00 the virtues of limC'Watcr, &c. p. 33. J9. 



