Intelligence and Miscellaneous Articles. 529 



2. The reciprocal action of two homogeneous bodies is of the 

 same nature. 



3. When an atom of A combines with several atoms of B, the 

 latter arrange themselves in such a manner that the reciprocal action 

 becomes a minimum. 



When in a combination of two heterogeneous bodies the recipro- 

 cal action is represented by a, and the reciprocal action of the homo- 

 geneous atoms by ft, taking n and m to signify the coefficients de- 

 rived from the number of atoms B, r for the distance, and /(?«') for 

 some function of heat, &c., we arrive at the following equation : — 

 ■nicx. + n/3 r, . 



As regards heat, I find a posteriori, that r is equal to the product 

 of the mass of the combination and the specific heat ; /(w) is equal 

 to the elevation of temperature. As to light, I h.ive abstained from 

 determining f{io), because the fundamental experiments are still 

 wanting. 



I could only make use of three experiments to check the correct- 

 ness of my calculation, because all others at present known only 

 furnish two numbers of atoms of B in a series ; or it was necessary 

 to determine the latent heat by calculation, for which purpose the 

 data are still wanting. The three series of which I have been able 

 to make use are, the combinations of sulphuric acid with water de- 

 termined by Favre and Silbermann, and those of hydrate of potash 

 with arsenic and j)hosphoric acids determined by Graham. 



To my great satisfaction I find that these experiments agree, as 

 nearly as could be desired, with the formula which I have employed. 

 1 obtained the relative numbers which express the affinity of the 

 bodies which were experimented upon. The affinitj'' between the 

 alkali and the arsenic acid is nearly equal to the affinity between 

 this base and phosphoric acid, but the distance between the atoms 

 of the base and those of the acid is 1 for arseniate of jiotash to v 2 

 for the phosphate of potash. The affinity between sulphuric acid 

 and water in comparison to that of these two salts is only as 

 208 : 860.— Comptes Rendus, April 17, 1854, p. 750. 



NOTE ON THE MAGNETISM OF LIQUIDS. BY M. QUET. 



M. PlUcker's method of ascertaining whether a liquid be magnetic 

 or diamagnetic does not always furnish very well-marked results, 

 especially with diamagnetic fluids. It appears to me that this may be 

 effected in a simple and direct manner by the following experiment. 



A slender glass tube containing a long column of the fluid to be 

 tried is placed between the poles of one of M. RuhmkorfF's electro- 

 magnets ; it is placed perpendicularly to the line of the ])oles in an 

 horizontal direction, and the commencement of the liquid index is 

 brought very close to the polar pieces. As soon as the electro- 

 magnet is set in action by a galvanic current, if the column of fluid 

 be magnetic, it advances tiie whole length of the polar pieces, and 



Phil. Mag. S. 4. No. 48. Suppl. Vol. 7. 2 N 



