264 Analyfis of the Air. 



phureous grofs vapours, or whether it was 

 occaftoncd by fome unheeded paffagefor the 

 air thro' the ligatures, I am uncertain ; nei- 

 ther did I care to afcertain the matter by re- 

 peated Experiments, fearing I might thereby 

 fome way injure my lungs, by frequently 

 breathing in fuch grofs vapours. 



Hence Sal Tartar fhould be the beft pre- 

 fervative againft noxious vapours, as being a 

 very ftrong imbiber of fulphureous, acid and 

 watry vapours, as is fea fait alfo : For ha- 

 ving carefully weighed the 4 'Diaphragms, 

 before I fixt them in the inftrument, I found 

 that they had increafed in weight 30 grains 

 in five minutes ; and it was the fame in two 

 different tryals 5 fo they increafed in weight 

 at the rate of 19 ounces in 24 hours. From 

 which deducting £ part for the quantity of 

 moifture, which I found thofe ^Diaphragms 

 attracted in 5 minutes in the open airs there 

 remains 1 5 -\- f ounces, for the weight of 

 the moifture from the breath in 24 hours : 

 But this is probably too great an allowance, 

 conftdering that the ^Diphragms might at- 

 tract more than ? part from the moifture of 

 the bladders and of the fyphon. 



I have 



