388 Intelligence and Miscellaneous Articles. 



Hyperiodate of Potash. — This salt may be obtained by adding 

 potash or its carbonate to iodate of potash and passing chlorine into 

 the solution: it is then precipitated in small white crystals, which 

 are difficultly soluble in water, and in appearance greatly resemble 

 hyperchlorate of potash. 



This salt appeared to be composed of 



One atom of hyperiodic acid. ... 182 

 One atom of potash 48 



230 

 A subhyperiodate of potash was obtained by adding potash to 

 the above, and evaporating the solution : white crystals were ob- 

 tained, which were not more difficult of solution than the neutral 

 salt. It appeared to consist of 



One atom of hyperiodic acid... . 182 

 Two atoms of potash. 96 



278 

 It is then an anhydrous dihyperiodate. 



Hyperiodate of Soda. — The neutral salt was obtained by dis- 

 solving the subsalt in hyperiodic acid to saturation. The solution 

 yields a white salt by evaporation, which dissolves readily in water, 

 and is unalterable in the air. It consisted of 



One atom of hyperiodic acid. . . . 182 

 One atom of soda 32 



214 

 Subhyperiodate of Soda. — This consisted of 



One atom of hyperiodic acid. ... 182 



Two atoms of soda 64 



Three atoms of water 27 



273 

 This salt is therefore a dihyperiodate. — Ann. de Chim. et de Phys., 



torn. liii. p. 92. 



CRYSTALLIZATION OF SULPHURET OF LEAD. 

 M. Becquerel has succeeded in forming and crystallizing sulphu ret 

 of lead, by means of a liquid and two substances, so placed that an 

 electric current results from their reciprocal action. He put into a 

 tube, about four inches long, one quarter of an inch in diameter, and 

 closed at one end, sulphuret of mercury to the height of about one 

 inch ; upon this a solution of chloride of magnesium was poured, and 

 a plate of lead was immersed to the bottom of the tube : the appara- 

 tus was then hermetically sealed. In about a month or six weeks, a 

 very small stratum, of a metallic grey brilliant precipitate, began to 

 appear on the sides of the tube, under the sulphuret : this was easily 

 detached, and gradually other small crystals appeared. These cry- 

 stals, examined with a glass, were found to be tetrahedrons, having the 

 appearance of galena. When the tube was opened, gas was evolved, 

 which had the smell of the compounds of sulphur with chlorine and 

 with hydrogen. On examining, a short time afterwards, the liquor 



