76 Intelligence and Miscellaneous Articles. 



strata of hydrated peroxide of iron, which is largely and intimately 

 mixed with the wad, so as not to be separable from it. 



According to analysis, 1 00 parts of the Derbyshire Wad were re- 

 solved into Peroxide of iron 52*34 



Deutoxide of manganese 385 9 



Water 1029 



Baryta 5*40 



Insoluble earthy matter 274 



99-36 



The Wad from the Harz, of which Klaproth has given an analysis 

 in the 3rd volume of his Contributions, appears to have been of the 

 same nature as the preceding ; but it contained a greater proportional 

 quantity of manganese and baryta. 



Third species of Wad. 



Another species of Wad ; of the exact locality of which I am ignorant, 

 was lately sent me from Germany, under the name of ochreous Wad, 

 by Professor Hausmann. It is a friable earthy substance, like the 

 foregoing species ; but the colour of its streak and powder is dark 

 or blackis i brown. It is very porous, and emits a copious stream of 

 air-bells when put into water. Its specific gravity is 4*506. 



On exposure to a red heat, after being dried at a temperature of 

 212° P., it loses 3*08 per cent, of water, together with oxygen gas. 

 Its loss at a white heat amounted to 12755 per cent.; namely, 3 - 08 

 of water, and 9 675 of oxygen. In muriatic acid it is readily dis- 

 solved with free disengagement of chlorine, leaving merely traces of 

 insoluble matter. The solution was free from lime and iron, but 

 contained a trace of baryta. Considering its high specific gravity, 

 the small quantity of combined water, and the large quantity of ox- 

 ygen, which it loses at a white heat, there cannot be a doubt that 

 this species of wad consists essentially of the anhydrous peroxide of 

 manganese, with which a small quantity of some hydrated oxide, pro- 

 bably manganite, is casually intermixed. — Brewster's Journal. 



ORGANIC TEXTURE OF VEGETABLE FOSSILS. 



Mr. Witham, of Lartington, who has for some time been occupied 

 in examining the vegetable remains which occur in our coal-fields 

 and other formations, intends to lay before the public the results of 

 his investigations. A method has been discovered by which the in- 

 ternal structure of these plants may be exposed to view in a most 

 satisfactory manner*', and a series of microscopic drawings made from 

 sections of the fossils is in the course of being engraved. It has 

 been denied that any vegetables of the dicotyledonous class exist in 

 the coal formation, but Mr. Witham hopes to be able to demonstrate 

 the fallacy of this opinion. The plates will be accompanied by re- 

 marks on the nature of the plants, and an account of their geological 

 position, and of other circumstances relative to their history. 



ACADExMIA CiESAREA NATURAE CURIOSORUM. 



We have been authorized to state, for the information of the mem- 



* See our present Number, p. 20. — Edit. 



bers 



