Comparison of the Blowpipes of Hare and Brook. 87 

 CHEMISTRY, PFIYSICS, MECHANICS, AND THE ARTS. 



Art. XIIL— f/po7i the fusion of various refractory bodies 

 by Hare's Blowpipe. 



(Translated from the Annales de Chimie et de Physique of Pahis, for July, 

 1820— Editors Gay Lussac and Arago.) 



The blowpipe of Hare was described in the Annals of 

 Chemistry, (Vol. 45, p. 113.) It is supplied by two 

 streams, one of hydrogen and the other of oxigen, which do 

 not mix till the moment of their combustion, and conse- 

 quently are attended by no kind of danger. This blowpipe 

 is in this respect far preferable to that of Newman, or rath- 

 er of Brook, who appeal's to have been the first inventor, 

 and it is not inferior to it, or only in a very shght* degree, in in- 

 tensity of heat. We can besides supply it with hydrogesf 

 gas and oxigen gas, compressed each in its own resen c'r ; 

 but, if we were to judge of it by the effects produced by ibis 

 instrument, and by that of Brook, there is but little advan- 

 tage in having recourse to this means. 



The simplest mode of constructing Hare's blowpipe in a 

 laboratory, would be, by taking two cylindrical bell glasses, 

 furnished virith stop cocks, the horizontal sections of which 

 (the glasses) should be such, that the one should present a 

 surface double to that of the other: they are to be fixed in 

 the pneumatic cistern, the largest to contain oxigen and the 

 smallest hydrogen. From each of the bell glasses should 

 proceed a tube, which should terminate in a somewhat mas- 

 sive cone of platina, perforated with two small ducts, very 

 near to each other, and corresponding to the two tubes. 

 The cistern being supposed to be filled with water, and the 

 bell glasses immersed in it, the gas will escape from them 

 by opening the stop cocks, always in the proportion to form 

 water, which is the best adapted to produce the maximum 

 of heat. 



* Whether it is inferior even in tfie slightest degree, may be seen from the 

 iJetalled comparison of result?} made by Professor Hare, in our last Number, 



---Editor. 



