Chemical Science. 399 



31. PRESENCE OP MANGANESE IN THE BLOOD. (Professor Wurzer, 



of Marburg.) 



In some analyses of human blood, according to Engelhart's method, 

 by liquid tests, Prof. W. was led to suspect that, besides the usual re- 

 sults, he had also obtained a small quantity of manganese : not being, 

 however, quite sure of the correctness of his analyses, he was induced 

 to repeat them in the following manner : The blood, which had been 

 obtained by venesection, on the day before the experiment, was 

 ignited in an open crucible, the incinerated mass oxidized by nitre, 

 and then diluted with water ; the residuum was dissolved in muriatic 

 acid, and the iron precipitated from the solution by succinate of am- 

 monia. As the precipitate contained also some phosphate of lime, 

 it was again ignited, and then dissolved in muriatic acid : the phos- 

 phate of lime was separated from the solution by alcohol, the excess 

 of the latter expelled by heat, and the iron precipitated by ammonia. 

 By boiling the filtered liquid with carbonate of soda, the manganese 

 was precipitated, and then dissolved in nitric acid and again ignited. 

 In two grammes of the coal was found 0.108 ox. of iron, and 0.034 

 protox. of manganese*. 



32. ON TWO ORES OP TELLURIUM FROM THE ALTAI MOUNTAINS. 



(M. Rose:) 



During the journey through Russia and Siberia, which M. Rose, of 

 Berlin, lately made in the company of MM. Humboldt and Ehrenberg, 

 he found two ores of tellurium in the silver mines of Sawodinski, 

 near those of Siranowski, at the river Buchtharma, and as this metal 

 has hitherto been only found in the gold mines of Transylvania and 

 in Norway, this discovery is of the greatest interest. We extract the 

 description of tellurium-silver and tellurium-lead as it is given by 

 M. Rose in Poggendorf's Annalen. 



He first saw these two ores in the Museum of the town of Bar- 

 noul, near the river Ob ; besides numerous smaller pieces, there were 

 two large blocks of about a cubic foot each, which, on account of 

 their malleability and the large quantity of silver they contained, 

 were considered to be silver-glass, from which they, however, were 

 found to differ greatly. Tellurium-silver is of granular texture, not 

 crystallized nor cleavable ; has much metallic lustre, and its colour 

 is between that of lead and steel : it is malleable, though to a less 

 degree than silver-glass ; and its specific gravity was found, by two 

 different experiments, to be 8.565 and 8.412. The specimens which 

 were examined by M. Rose were adhering to greenish-grey talc slate, 

 and the ore was mixed with black blende, small quantities of sulphate 

 of iron and of copper, and tellurium-lead. 



When tellurium-silver was heated before the blowpipe on charcoal, 

 it fused to a black mass, which, on cooling, became covered with 



* Poggeudorff s Afihi der Pbysik und Chemie, 



2D2 



