8o HISTORICAL INTRODUCTION TO CHEMISTRY CHAP. 



c. Sulphur introduced into it when burning with a 

 feeble blue flame, was instantly extinguished ; but when in 

 a state of active inflammation ... it burnt with a beautiful 

 and vivid rose-coloured flame. 



//. Inflamed charcoal . , . burnt with much greater 

 vividness than in the atmosphere. 



e. To some fine twisted iron wire a small piece of cork was 

 affixed : this was inflamed, and the whole introduced into 

 a jar of the air. The iron burned with great vividness, and 

 threw out bright sparks as in oxygen. 



f. 30 measures of it exposed to water previously boiled, 

 was rapidly absorbed ; when the diminution was complete, 

 rather more than a measure remained. 



g. Pure water saturated with it, gave it out again on 

 ebullition, and the gas thus produced retained all its former 

 properties.. 



h. It was absorbed by red-cabbage juice ; but no alteration 

 of colour took place. 



/. Its taste was distinctly sweet, and its odour slight, but 

 agreeable. 



/. It underwent no diminution when mingled with oxygen 

 or nitrous gas (Davy's Works, III. 54). 



Davy (1799) uses " laughing gas " as an anaesthetic. 



Although the gas had been credited with the most deadly 

 properties, and with the power of producing plague and 

 other contagious diseases, Davy found from personal 

 experiments in the spring of 1799 that it could be breathed 

 without harm, and had indeed remarkable stimulating and 

 exhilarating qualities. Robert Southey, one of many friends 

 who submitted themselves to the action of the new. 

 intoxicant, describes his feelings as follows : 



" My first definite sensation was a dizziness, a fullness in 

 the head, such as to induce a fear of falling. This was 

 momentary. When I took the bag from my mouth, I 

 immediately laughed. The laugh was involuntary, but 

 highly pleasurable, accompanied by a thrill all through me ; 

 and a tingling in my toes and fingers, a sensation perfectly 

 new and delightful " ( Works, III. 301). 



