Harems Calorimotor. 421 



That a peculiar combination between heat and light exists in 

 the solar beams, is evident from their not imparting warmth to 

 a lens through which they may pass, as do those of our culinary 

 fires. 



Under this view of the case, the action of the poles in Gal- 

 vanic decomposition is one of complex affinity. The particles 

 of compounds are attracted to the different wires agreeably to 

 their susceptibilities to the positive and negative attraction, and 

 the caloric leaving the electric fluid with which it had been 

 combined, unites with them at the moment that their electric 

 state is neutralized. 



As an exciting fluid, I have usually employed a solution of 

 one part sulphuric acid, and two parts muriate of soda with 

 seventy of water ; but, to my surprise, I have produced nearly 

 a white heat by an alkaline solution barely sensible to the taste. 



For the display of the heat effects, the addition of manganese, 

 red lead, or the nitrates, is advantageous. 



The rationale is obvious. The oxygen of these substances 

 prevents the liberation of the gaseous hydrogen, which would 

 carry oft' the caloric. Adding to diluted muriatic acid, while 

 acting on zinc, enough red lead to prevent efiervescence, the 

 temperature rose from 70 to 110 Fahrenheit. 



The power of the calorimotor is much increased by having 

 the communication between the difierent sheets formed by 

 very large strips or masses of metal. Observing this, I ren- 

 dered the sheets of copper shorter by half an inch, for a 

 distance of four inches of their edges, where the communica- 

 tion was to be made between the zinc sheets ; and, vice versa, 

 the zinc was made in the same way shorter than the copper 

 sheets where these were to communicate with each other. 

 The edges of the shortened sheets being defended by strips of 

 wood, tin was cast on the intermediate protruding edges of the 

 longer ones, so as to embrace a portion of each equal to about 

 one quarter of an inch by four inches. On one side, the tin 

 was made to run completely across, connecting at the same 

 time ten copper and ten zinc sheets. On the other side there 

 was an interstice of above a quarter of an inch left between 

 the stratum of tin embracing the copper, and that embracing 



