J280 Intelligence and Miscellaneous Articles, 



with advantage, I cannot offer an opinion until I have madeaquan" 

 titative determination. It is probable that the acid exists in combina- 

 tion with soda, as in the waters occurring in Cliina, Persia and Peru. 

 In the water of the Tuscan lagoons, on the contrary, it is in a free state. 

 The alkalinity of thermal waters issuing from granitic rocks and 

 containing silica in solution, frequently in considerable quantity, 

 induces me to conjecture that they likewise contain boracic acid. I 

 shall for the present limit myself to pointing out its existence in the 

 waters of Olette, and on a future occasion will resume this subject. 

 — Comptes Rendus, January 1853, p. 239. 



ON THE PRESENCE OF BORACIC ACID IN THE MINERAL WATERS 

 OF WIESBADEN AND AIX LA CHAPELLE. BY R. FRESENIUS 

 AND R. WILDENSTEIN. 



It was not improbable that some thermal waters contain boracic 

 acid as the waters of cold springs contain, besides iron, manganese 

 and zinc, but hitherto there was no sufficiently delicate test for this 

 acid, and in many cases it was not sought for in the analysis of ther- 

 mal waters. Taking advantage of the process recommended by H. 

 Rose, Professor Fresenius has succeeded in detecting boracic acid in 

 the water of the " Kochbrunnen," at Wiesbaden, and this result in- 

 duced Wildenstein, one of his pupils, to examine the water of the 

 Kaiserquelle at Aix la Chapelle, which was also found to contain it. 

 '•—Journ. jur Prakt, Chem. vol.lv. pp. 163, 1G5. 



ON THE PER-CENTAGE OP ZINC IN BRASS AND BRONZE, AND THE 

 SEPARATION OF ZINC FROM COPPER. BY M. BOBIERRE. 



My researches on the composition of the alloys intended for the 

 sheathing of vessels have led me to examine the chemical compo- 

 sition of the brass used for the navy. I soon found that the separa- 

 tion of zinc from copper presents numerous difficulties, and that the 

 methods hitherto adopted are, if not insufficient, ac least ill-calculated 

 to furnish accurate results in all cases. 



The analytical method which I am about to describe is based upon 

 the known facts that zinc is volatile, and that its vapour is readily 

 carried off by a current of hydrogen. The alloy of copper and zinc 

 is exposed to a red heat for three-quarters of an hour or more in a 

 small porcelain tray, and a current of hydrogen passed over it. By 

 the application of this means in a great number of instances I have 

 invariably obtained results possessing a remarkable degree of accuracy. 



I have further ascertained that, under these circumstances, lead is 

 not volatilized, so that the presence of this metal in a specimen of 

 brass or bronze does not affect the accuracy of the results. Alloys 

 of zinc and iron may be analysed very rapidly by means of the above 

 j)TOce9S. — Comptes Rendus, January 1853, p. 224. 



ON THE PRESENCE OF SUGAR IN THE URINE OF EPILEPTIC 

 PATIENTS. BY MM. MICHEA AND ALVARO REYNOSO. 



That the urine passed by epileptics, after their attacks, contains 

 sugar, is a fact which has been proved by a great number of experi« 



