1 26 Notices respecti?ig New Books. 



shown before by Karsten), but probably also tantalium. As 

 both these metals are so scarce, especially tantalium^ I have 

 thought it of use to call the public attention to this slag. 



It is not improbable but that the titanium originated by re- 

 duction from prototitanate of iron and manganese, and the 

 tantalium from the tantalates of the same bases (tantalite). It 

 would be a very meritorious performance, and highly important 

 to the geology of Silesia, if any one would institute a strict ex- 

 amination ol the iron ore which yielded this slag, as well as of 

 its locality, and the process of smelting it undergoes. 'Perhaps 

 by so doing some pure tantalium, or combinations of that 

 metal, as well as of titanium (and perhaps wolfram), may be 

 found in larger or smaller quantities. It need scarcely be 

 mentioned, that titanium is found in the Riesengebirge of Si- 

 lesia, especially in the Iser (Iserin) in the shape of nigrin. 



XXIII. Notices respecting New Books. 



THE following are the Contents of those Parts lately published, 

 of the Philosophical Transactions, and of those of the Linnean 

 and Astronomical Societies : 



Philosophical Transactions for 1827. — Part 11. 



On a new form of the differential thermometer, with some of its 

 applications. By William Ritchie, A.M. — On the structure and use 

 of the submaxillary odoriferous gland in the genus Crocodilus. By 

 Thomas Bell, Esq.— On the permeability of transparent screens of 

 extreme tenuity by radiant heat. By William Ritchie, A.M. — On the 

 derangement of certain transit instruments by the effects of tempera- 

 ture. By Robert Woodhouse, A.M. — On some of the compounds of 

 chromium. By Thomas Thomson, M.D. — Rules and principles for 

 determining the dispersive ratio of glass j and for computing the 

 radii of curvature for achromatic object-glasses, submitted to the 

 test of experiment. By Peter Barlow, Esq. — On the change in the 

 plumage of some hen -pheasants. By William Yarrell, Esq. — On the 

 secondary deflections produced in a magnetized needle by an iron 

 shell in consequence of an unequal distribution of magnetism in its 

 two branches. First noticed by Captain J. P. Wilson. By Peter 

 Barlow, Esq.— On the difference of meridians of the royal observa- 

 tories of Greenwich and Paris. By Thomas Henderson, Esq.— On 

 some observations on # the effects of dividing the nerves of the lungs, 

 and subjecting the latter to the influence of voltaic electricity. By 

 A. P.W.Philip, M.D. — On the effects produced upon the air cells of 

 the lungs when the pulmonary circulation is too much increased. 

 By Sir Everard Home, Bart.— Theory of the diurnal variation of the 

 magnetic needle, illustrated by experiments. By S. H. Christie, Esq. 

 M.A. — On the ultimate composition of simple alimentary substances ; 



with 



