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VIII. On a new Form of Spirator. By Frederick Guthrie*. 



THE following form of spirator will be found useful in esta- 

 blishing a current of air for an indefinite length of time, 

 by means of a continuous current of water. It may be employed 

 either as aspirator in drawing, or as expirator in forcing air 

 through an apparatus. Its action will be readily understood by 

 referring to the accompanying diagram. 



A is a wide-mouthed 12-ounce bottle, whose bottom is covered 

 with a few millimetres of mercury, m. Through its well-fitting 

 cork C, four holes arc bored. Into the first of these, the wide 



* Communicated by the Author. 



