Scientific Intelligence — Geology and Mineralogy. 383 



for, on the one hand, cold hydrochloric acid separates peroxide of iron, 

 from the mineral, and leaves blue oxide of tungsten ; and, on the 

 other hand, the free protoxide of iron reacts on the tungstic acid 

 isolated, and reduces it to the state of the blue oxide, and itself be- 

 comes peroxide. 



When heated to ebullition in hydrochloric acid, the blue oxide, in 

 its turn, reduces the salts of iron, and this reaction explains how 

 Berzelius and Ebelmen adopted the first formula. 



The superior oxides of manganese convert the blue oxide into 

 tungstic acid, under the same circumstances as the peroxide of iron, 

 even when cold. This circumstance induced the author to suppose 

 that the manganese might exist as the oxide Mn^ 0^, isomorphous with 

 the sesquioxide of iron, although found only in the state of protoxide 

 in the solution of the mineral. 



M. Marguerite further observes, that it is easy to explain the 

 causes of the different opinions which have been given on the che- 

 mical constitution of Wolfram ; that it had not been deduced from 

 the very exact analyses already alluded to, is, because the last phase 

 of an operation was considered instead of its commencement. 



M. Marguerite concludes that, — 



l5{, The tungsten in Wolfram is in the state of blue oxide. 



2dy The iron is in the state of peroxide. 



3c?, The tungstic acid and protoxide of iron obtained are the re- 

 sults of the analytic means employed, and that these two products 

 are eventually formed from each other. 



4«A, Of the three formula; which have been given, the second and 

 diird only agree with experiments, and the second may be reduced 

 to W2 O^ 112 0^.— Jowm. de Ph. et de Ch., Octobre 1843.— PAz7o- 

 sophical Magazine^ Vol. XXIV., No. 157, p. 153. 



3. Analysis of Ancient and Fossil Bones. By MM. Girardin and 

 Preisser. — The authors found that human bones taken from various 

 ancient tombs contained from less than 1 up to 8 per cent, of phos-' 

 phate of magnesia; and in one case the bones of an infant taken from 

 a Gallo-Romantomb at Rouen, were found to be of a fine chrome-green 

 colour, and contained 3.1 per cent, of carbonate of copper, for the 

 existence of which no sufficient cause appeared. 



In ancient buried bones, as well as in the fossil bones of animals, 

 the authors always found a much greater quantity of phosphate of 

 lime than in recent bones. Under certain unknown circumstances, 

 this salt suffers some curious modifications, by which it is converted 

 into, for the most part, sesquiphosphate of lime, which crystallizes in 

 small hexagonal prisms on the surface of the bones. This transfor- 



