22 



CALORIFIC POWER OF FUELS. 



centimetres (about 8 inches) high and 12 centimetres (4 

 inches) in diameter. In the middle is placed the combustion 

 chamber A (Figs. 2 and 3). 



FIG. 2. FIG. 3. 



FAVRE AND SILBERMANN CALORIMETER. 



The combustion-chamber is of burnished gilt copper, and 

 is shown in Fig. 3. It is a slightly conical vessel, the large 

 opening in which receives a stopper from which is suspended 

 the burner made of a material suitable to that of the sub- 

 stance operated on. The stopper itself carries two tubes, m 

 and n, the first being an observation tube for the combustion, 

 and is surmounted by a mirror. M, which allows examination 

 during the burning. The mirror receives light by the tube 

 m, which is closed by an athermanous system of quartz, 

 alum, and glass. The other tube, #, carries the jet for the 

 oxygen. Tube b is closed, or removed during the test with 

 coal, as it is of no use then. Tube c serves as the exit for the 

 waste gases of the combustion, which pass through the coil cc 

 (Fig. 2) before reaching the analytical apparatus. This coil 



