154 COHESION OF LIQUIDS. 



more than doubtful among men of the soundest 

 views. 



That nitric, sulphuric, and phosphoric acids, 

 owe their active properties to the igneous prin- 

 ciple with which they are associated, cannot be 

 doubted ; as their action is attended with an in- 

 tense heat, as when mixed with oils, sugar, and 

 alcohol; and is accompanied by the formation of 

 new chemical compounds. It is the prevalent 

 opinion of medical men, that hydro-cyanic acid 

 destroys life by a sedative influence ; but I have 

 satisfied myself by inspecting the stomachs of 

 individuals who have been destroyed by it, that 

 it produces a high degree of active inflammation. 

 There never was a stomach more injected with 

 blood, than one exhibited in Guy's Hospital, pro- 

 duced by swallowing a large dose of prussic acid. 



It has been discovered by the recent researches 

 of chemists, that there are several combinations 

 of carbon and hydrogen, the relative proportions 

 of which are the same, while they differ greatly 

 in their physical properties: for example, olefiant 

 gas is composed of 2 atoms carbon, united with 

 2 of hydrogen, forming a bicarburet of hydrogen, 

 which is permanently elastic at all temperatures ; 

 while setherine is a quadri- hydro-carbon, con- 

 sisting of 4 atoms carbon, to 4 of hydrogen, united 

 into 1 compound atom, the weight of which is 28, 

 compared with hydrogen as unity ; or just double 

 the atomic weight of oletiant gas. Accordingly, 



