SCHARLING, EEGNAULT, AND REISET S APPARATUS. 



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hich is placed the dog to be experimented on (fig. 145). Around this is placed a cylinder, 

 g, g, (provided with a thermometer, t), which may be used for calorimetric experiments. A 

 tube, c, leads into the globe, R ; through this tube passes a known quantity of pure oxygen 

 (fig. 145, 0). To absorb any trace of C0 2 , a vessel containing potash (fig. 145, C0 2 ) is placed 





Fig. 144. 

 Scharling's apparatus, d, bulb containing caustic potash to absorb C0 2 from in-going air ; A, 

 box for animal experimented on ; e and g, tubes containing sulphuric acid to absorb 

 watery vapour ; /, potash bulb to absorb C0 2 given off ; C, vessel filled with water to 

 aspirate air ; h, stop-cock. 



in the course of the tube. The vessel for measuring the is emptied towards R, through a 

 solution of calcium chloride from a large pan (CaCl 2 ) provided with large flasks. Two tubes, 

 d and e, lead from R, and are united by caoutchouc tubes with the potash bulbs (KOH, Koh), 

 which can be raised or depressed alternately by means of the beam, W. In this way they 



Koh 



Fig. 145. 

 Scheme of the respiration apparatus of Regnault and Reiset. R, globe for animal ; g, g, outer 

 casing for R, provided with a thermometer, t ; d and <?, exit tubes to movable potash bulbs, 

 KOH and Koh ; 0, in-going oxygen ; C0 2 , vessel to absorb any carbonic acid ; CaCl 2 , 

 apparatus for estimating the amount of supplied ; /, manometer. 



aspirate alternately the air from R, and the caustic potash absorbs the C0 2 . The increase in 

 weight of these flasks after the experiment indicates the amount of C0 2 expired. The mano- 

 meter, /, shows whether there is a difference of the pressure outside and inside the globe, R. 



(c) V. Pettenkofer ha3 invented the most complete apparatus (fig. 146). It consists of a 

 chamber, Z, with metallic walls, and provided with a door and a window. At a is an opening 

 for the admission of air, while a large double suction-pump, PP X (driven by means of a steam- 



