78 Intelligence and Miscellaneous Articles. 



their electric conducting powers. Lect. VI. — December \&th. — 

 Union of forces in the phenomena of Geology and Physiology — 

 Theories of Causation — Ignorance of ultimate causation. Conclusion. 



XII. Intelligence and Miscellaneous Articles. 



PREPARATION OF HYPOSULPHITE OF SODA. BY M. WALCHNER. 



THIS salt, according to M. Walchner, is readily prepared and in 

 large quantity by the following process : — dry crystallized carbon- 

 ate of soda perfectly and reduce it to fine powder ; mix one pound with 

 five ounces of sulphur, and heat the mixture gradually in a porcelain 

 vessel until the sulphur melts ; the agglutinated mass being kept hot 

 is to be stirred in order that every portion of it may come into con- 

 tact with the air ; in this case the sulphuret of sodium formed is con- 

 verted into sulphite of soda, by absorbing oxygen from the atmo- 

 sphere. This salt is to be dissolved in water, the filtered solution is 

 to have sulphur boiled in it, and the filtered liquor, which is nearly 

 colourless when much concentrated, yields very pure and fine cry- 

 stals of hyposulphite of soda in large quantity. 



When the temperature is too rapidly raised a small quantity of 

 sulphur burns readily ; a portion of carbonate of soda then remains 

 unacted upon and destroys the purity of the crystals of hyposulphite 

 first obtained ; but it is easy to separate the impurity. — Journ. dePh. 

 et de Ch„ Octobre 1843. 



ON THE ACTION OF CHLORIDES UPON PROTOCHLORIDE OF 

 MERCURY. BY M. MIALHE. 



In vol. xxi. pp. 320 and 492 of the L. and E. Phil. Mag. S. 3 will be 

 found the results of M. Mialhe's experiments on the above subject, 

 and in vol. xxiii. p. 233 we gave the results of M. Larroque's expe- 

 riments on the same subject, and of the different conclusions at 

 which he had arrived from those maintained by M. Mialhe. M. 

 Mialhe, still retaining his opinions, has published some further re- 

 marks on the subject ; and on the opinions of M. Larroque he ob- 

 serves, that while M. Larroque admits that protochloride of mercury 

 is dissolved by the alkaline chlorides at common temperatures, he 

 denies that it is converted into bichloride, but is held in solution as 

 protochloride. 



In support of his opinion M. Mialhe states an experiment which 

 positively determines that the mercury exhibited in this case by hy- 

 drosulphuric acid or the hydrosulphates, is not in the state of proto- 

 chloride. He observes that an excess of these reagents completely 

 redissolves the precipitate they occasion, which could not happen if 

 the salt were a protosalt. 



In concluding his reply to M. Larroque, M. Mialhe states, — 1st. 

 That, contrary to the assertions of Hervy, MM. Caventou, Larroque, 

 &c, protochloride of mercury is partly converted into bichloride by 

 the influence of aerated alkaline chlorides, at common temperatures. 

 2nd. That the mercurial compound which is then formed is not, 

 however, identically the same as that which is produced when the 



