Miscellanies. 377 



of chemical phenomena may be remarked by the small quantity of 

 electricity, and the great tension in proportion to it. Independent of 

 chemical phenomena, they may possibly depend upon the unequal 

 conducting power of the metals employed, and their consequent un- 

 equal capacity for electricity in its distributed or polarized state, 

 which must be greater in good than in bad conductors."— Edinb. 

 Jour, of Science, July, 1830. 



9. Heat of the Planetary Space.— U is known that Fourier, in his 

 valuable researches into this subject, deduced from the laws of radi- 

 ant heat that the temperature of the planetary space is — 50° cent. 



58° Fahr., and that the earth has nearly reached its limit of cool- 

 ing. Suanberg has built his researches upon a different principle, and 

 has obtained the same result. From his letter to Berzelius on this 



subject, we extract the following : 



" Led by these considerations, and by the many known affinities 

 between light and heat, which are especially remarkable in the ac- 

 knowledged property of solar light, to develope heat in opaque and 

 imperfectly transparent bodies, I began by supposing that the plane- 

 tary space (considered as perfectly pellucid,) never undergoes any 

 change of temperature, either from the action of light or of radiant 

 caloric, and that, therefore, the capacity for elevation of temperature 

 above what reigns in the ethereal regions, can exist only within the 

 limits of the planetarv atmosphere. Further, that the rapidity of the 

 change of temperature at an indefinite height above the surface of the 

 earth, is alwavs proportional to the rapidity of the atmosphere's cor- 

 responding change of capacity to absorb light. In this way I obtain- 

 ed the temperature of the atmosphere, (expressed in a function of an 

 indefinite height above the earth's surface,) containing only two arbi- 

 trary constants, of which the one is also a function of the time, and 

 is determined always by immediate observation of the given tempera- 

 ture at the moment on the earth's surface ; the other, namely, the 

 temperature of the plnnetary space, is constant, even in regard to the 

 time. The numerical solution presupposes accurate observat.ons of 

 temperature at isolated points to a considerable heigh above the 

 earth's surface, which, however, are unfortunately so extremeh few 

 that we can have recourse among newer observations to -but a s ngk 

 one, that of Gay-Lussac, in his aeronautic expedition. 1 « ere to be 

 wished that the same experiments were repeated, I»^«hrly £ ^ 

 neighborhood of the equator, where the o-iHations around the m^ an 

 state of the atmosphere, and consequently the P?^j£™%£ 

 accidental circumstances are less to be dreaded. In the me an ime^ 

 availin. myself of this observation, I have obtained for the planetary 



