Manchester Memoirs, Vol. xlvti. (igoTf), No. 15. 9 



gallon, when working with 50 c.c, that is, one part in 

 140,000,000 parts of liquid, and half that amount can 

 be detected, that is, i part in 280,000,000, which is 

 equivalent to i grain of arsenic trioxide dissolved in 4,000 

 gallons of beer, i.e., i grain dissolved in iii barrels of 

 beer of 36 gallons each, which is equivalent to 18 tons 

 weight of beer. 



