[ 148 ] 

 XXII. Intelligence and Miscellaneous Articles. 



ON THE "aNTRIMOLITe" OF THOMSON. BY DR. HEDDLE. 



THE "Antrimolite" of Thomson, in which that chemist found 4' 10 

 per cent, of potash, I make mesolite, finding sorfa instead of potash. 

 Of the specimens analysed, the second was procured from Mr. 

 Doran, who supplied Dr. Thomson ; for the third I am indebted to 

 the kindness of Mr. Rose ; — these facts are mentioned that there 

 may be no doubt of its being Antrimolite that was examined. 



25 grains of each. 



I. II. III. 



Silica 47-072 45-98 46-13 



Alumina 26228 26-18 26-48 



Lime 9-885 10-785 not det. 



Soda 4-886 4-542 not det.* 



Water 12-237 13-00 14-20 



100-308 100-487 



This is evidently mesolite (see Philosophical Magazine for January) ; 

 Dr. Thomson's analysis, however (after substituting soda for potash), 

 seems to point rather to Faroelite. The third specimen was somewhat 

 contaminated by carbonate of lime, calc-spar being the basementf. 



ON THE MAGNETISM AND ELECTRICAL CONDXTCTIBILITY OF 

 POTASSIUM AND SODIUM. BY M. LAMY. 



It has often been attempted to discover a relation between the 

 atomic weights and volumes of bodies and some of their phj'sical 

 properties, such as their density, crystalline form, boiling-points, 

 specific magnetism, &c. With regard to the latter property, it is 

 generally admitted that the most magnetic metals are those which 

 have the smallest atomic volume, and vice versd. 



The author has drawn up a table of the principal metals with their 

 densities, chemical equivalents, and atomic volumes. From this it 

 appears that there are numerous exceptions to the supposed law, and 

 that sodium, and especially potassium, ought to be much more dia- 

 magnetic than bismuth itself. 



According to Faraday, sodium and potassium are diamagnetic. 

 The author's experiments show that these metals are feebly magnetic. 

 Taking every precaution that the masses experimented on should be 

 free from iron, he always found that at the moment of closing 

 the circuit of RuhmkorfFs electro-magnet there was a considerable 

 repulsion, due to the production of induced currents in the mass 

 affected, followed by a manifest and permanent attraction when the 

 electro-magnet had attained its state of magnetic equilibrium. The 

 attraction took place with a globule of potassium extracted directly 

 by the pile, without the intervention of mercury, from a potash which 



* Potash traces, and some CO^. 



t Errata in last paper. There was a misplacement of figures in the 

 Table at p. 65. The formulse for Fargite and FaroeUte should be — 



Fargite (2NaO, CaO), 3SiO'-f 3(A1- O', SiO^) + 7HO. 



Faroelite (NaO, 2CaO), 2SiO='-|-3(AP03, Si03)-}-8HO. 



