Account of "Mr. Smith's Air-pump rapour-lath. 297 



machine. B the boiler containing the fluid, the fumes of 

 whic!) are thrown into the cyhnder, through the ftop-cock H, 

 and heated by means of a fpirit lamp C, which ought always 

 to be withdrawn immediately on turning the ftop-eock G, 

 hereafter mentioned. D a thermometer, Ihowing the tem- 

 perature of the fumigation. E the exhauller for producing 

 a partial vacuum within the cylinder, after the fumigation has 

 continued a proper time. F the efcape-valve of the exhauller, 

 to which a flexible pipe is adapted to convey the air from the 

 chamber, if vitiated by the nature of the afie6tion for which 

 the application is made. G the ftop-cock of the boiler. 

 II another ftop-cock to prevent the valves of the exhauller 

 from being injured by the hot funics, as they enter the ma- 

 chine during the fumigation. 



Fig. 2. a perfpeftive view of the machine from the other 

 end, where the limb is admitted. I the body of the machine, 

 made of ftrong copper tinned in the infide, ordinary tinned 

 iron itfelf not l3cing fufficient, in all cafes, to refift the prelTure 

 of the atmofphcre. K the mouth of the machine, to which 

 is attached a ftrong bladder, cut fo that one end of it may go 

 over, and be firmly fccured to it by means of a ligature; the 

 other fo that it may be drawn over the limb, when paflTcd 

 through it into the machine, and fecurcd upon it by means 

 of a roller. 



The conftruftion of the machine juft dofcribed, is adapted 

 to the leg or arm only. Its principle, however, may be ex- 

 tended, and one might be made to include a greater portion 

 of the body. Such an attempt is making. One of the mod 

 obvious confequences of its application muft be, a temporary 

 expanfion of the veflels of the part from whence fo great a 

 prelfure is removed, 'i'his muft powerfully affift nature in 

 removing obftruftions formed in them, which often fpccdily 

 produce inflammation, and terminate in fuppuration and 

 abfcefs. 



Dr. Hamilton, of the London Difpenfary, has obfervcd, 

 that the mode in which it U)uft at'^t is agreeable to found the- 

 ory, !i\M.\ that the more it is applied to praAicc, the oltcner 

 will facts occur to rec':mnKMid it. 'i'hat eminent phyfician 

 ♦' not only views it as valuable to remove local aft"e6lions ot 

 the extremities, but alio to allbrd relief in other parts ot the 

 body, where obftru^lions may have taken place." In the 

 (•inie lirtter he oblerves, that " the machine, by having a 

 condenling pump fixed to n, may be nied as a bracer, and 

 that with beneficial and pciweilul ene«5ts." 'i'his may be 

 done merely by rcvcrliug the valves in the pump. 



Thcfe 

 6 



