298 I\lemoir en the Supply and. 



Thefe confiderations, however, [ (liall leave to your me- 

 dical readers, to whom I wifli to fubmit this important query 

 — Is the applicatio7i of the pr'mciple juji alluded to, ever likely 

 to be ofuj'e in relieving the ruptured? 



Mo. 5, Cumberland Place, I am, Sir, VOUrS, 8cc. 



New Road, Marylebone, He'nRY JaMES, 



January S, 1S03. 



XLVII. Memoir on the Supply and Application of the Blow- 

 pipe. By Mr. Robert Hare jun. Member of the 

 Chemical Society of Philadelphia. 



[Concluded from p. 245. 1 



A HE hydroflatic blovi^-pipe may be filled with any of 

 the gafes, by exhauding them from the inverted jars of the 

 pneuuiato-chemical apparatus : and if it be defircd to confine 

 different fpccies of gas, by clofing the cock of communica- 

 tion between the compartments, one of them may be filled 

 xvith one kind of gas, and afterwards, by turning the hood, 

 the other compartment may be filled with another kind. To 

 make this underftood, let a, fig. 5, be a pneumato-chemical 

 tub, with a flielf c, and an inverted glafs jar b. Suppofe 

 that the tub were filled with water, and the jar with gas. 

 Lute the pipe J, fig. i, to the mouth of the fuftion-pipe at I; 

 pafs thefyphon L under the jar, as may be obferved in fig. 5, 

 and then extend the bellows. The bellows will become filled 

 with the air of the jar; and this being difcharged into that 

 compartment of the calk which is over the open fide of the 

 hood, the bellows will be ready for another extenfion ; the 

 repetition of which would foon exhauft the jar of its air, al- 

 though it fliould be of the largeft fize. 



This method of filling the machine is very convenient in 

 a laboratory well fupplied with pneumato-chemical apparatus. 

 But it is a principal convenience of the hydroftatic blow-pipe, 

 that it may be filled with any gas, immediately from the re- 

 tort, bottle, or matrafs, made ufe of in obtaining it. Let D, 

 fig. 6, be a feparate reprefentation of the pipe D, fig. i. 

 Let B be a matrafs containing the fubftance from which the 

 air is to be obtained, and let C be a fyphon luted to the neck 

 of the matrafs. The air iffuing from the matrafs muft be 

 emitted from the mouth of the fyphon at the lower end of 

 the pipe D. Suppofe that this pipe were in its proper fitua- 

 tion at D, fig. i, the air iffuing from the mattafs would be 



difchargvd 



