or hinder the artificial Produ&ion of 

 Cold by particular Agents , but, 

 which will feem more ftrange, fome 

 unobferv'd, and perhaps hardly ob- 

 fervable, Indifpofition in the Patient 

 may promote or hinder the effe&s-of 

 the grand and Catholick Efficients of 

 Cold, whatever thofe be. This fuf- 

 picionl reprefent as a thing that fur- 

 ther experience may poffibly coun- 

 tenance , becaufe I have fotnetimes 

 found, that the degree of the Ope- 

 ration of Cold has been much vari- 

 ed by latent Circumftances 7 fome 

 bodies being more wrought upon, 

 and others lefs^ than was upon very 

 probable grounds expe&ed. And 

 particularly I remember, that though 

 Oyl of Vitriol be one of the firieft 

 liquors that is yet known^ and does 

 perform fome of the Operations of 

 fire it (elf, (as we (hall elfewhere 

 have occafion to (hew) and will thaw 

 Ice (boner than Spirit of Wine or a- 

 ny other liquor, as I have tried i yet 

 having put about a pound or more 5 

 by our eftimate, of choice re$ified 

 C 3 Oyl 



