334- Intelligence and Miscellaneous Articles. 



sipate the last traces of carbon which the filter may have left. In 

 this manner the water may be ascertained by simple calcination, the 

 tungstic acid directly, and the alkali by difference. 



Having attempted to estimate the alkali by the quantity of sul- 

 phuric acid fixed, it was found that tungstic acid, like the silicic and 

 boracic acids, decomposed the neutral sulphate at the temperature 

 requisite to destroy the bisulphate : the tungstic acid then combines 

 with the alkali, and forms a tungstate which is more or less acid ; it 

 is therefore important not to carry on the operation so far. The bi- 

 sulphate possesses the advantage of presenting sulphuric acid to 

 those parts of the salt which would not be decomposed, which at this 

 high temperature acts energetically. 



That the salt has been completely attacked, and that the tungstic 

 acid has not been hydrated, and consequently dissolved, may be as- 

 certained by treating the first washings with a plate of zinc and hy- 

 drochloric acid. They do not in this case produce the slightest blue 

 tint, though capable of ascertaining the smallest quantity of tungstic 

 acid. — Ann. de Ch. et de Phys., Aout 1846. 



PREPARATION OP CHLORIC ACID. BY M. BOETTGER. 



The author observes, that the preparation of chloric acid by means 

 of hydrosilicic acid is attended with a great number of inconve- 

 niences ; he therefore proposes to replace it with oxalic acid, this 

 acid also yielding a salt of soda which is but slightly soluble in 

 water. 



The following is the process recommended. First prepare a solu- 

 tion of tartrate of soda, by dissolving seven parts of crystallized car- 

 bonate of soda and seven and a half parts of tartaric acid in boiling 

 water ; add to this solution while boiling a solution, also boiling, of 

 six parts of chlorate of potash in sixteen parts of water : let it cool, 

 so as to allow the tartar to deposit ; then filter, and add to the solu- 

 tion six parts of oxalic acid dissolved in six parts of water, heated 

 to a temperature not exceeding 133° F. ; agitate the mixture briskly, 

 and put it into a freezing mixture, made with crystallized sulphate 

 of soda and muriatic acid ; by this the oxalate of soda is deposited, 

 and it requires only to be separated by the filter. 



The chloric acid thus obtained is not chemically pure ; but to pro- 

 cure it pure and concentrated, it is to be treated with recently preci- 

 pitated carbonate of barytes, crystallizing the chlorate formed, and 

 decomposing it with sulphuric acid. — Journ. de Pharm. et de Ch., 

 Juillet 1846'. 



OBSERVATIONS ON YEST. 



M. F. W. LudersdorfF, in order to decide the question whether 

 yest is an organized substance, and whether, if it be, it occasions 

 fermentation in consequence of it, made the following experi- 

 ments : — He triturated a portion of it on glass so perfectly, that 

 the microscope could not detect any kind of globular texture ; 

 two parts of grape-sugar were dissolved each in ten parts of 



