176 ANNUAL OF SCIENTIFIC DISCOVERY. 



charged with soluble organic matter, in the state of crenic, apocrenic, 

 or huniic acids, drained into them in consequence of rains or inunda- 

 tions, from swamps and peat meadows, the carbonates of lime and 

 manganese enter into solution. At such times manganese may gener- 

 ally be detected in these waters, as has been done by Drs. C. T. Jack- 

 son, A. A. Hayes, and others. When the water holding the manga- 

 nese in solution, becomes broken and thrown up in the passage of falls 

 or rapids, consequently exposing it to the influence of the atmosphere, 

 the manganese passes from a low state of oxidation to the insoluble 

 peroxide, and is deposited for a considerable extent upon the rocks and 

 pebbles below. It will thus be found, upon examination, that, at inter- 

 vals in the bed of the stream, the stones are completely blackened or 

 discolored, while in other places no such depositions exist. Beautiful 

 examples of this phenomenon may be seen at some points on the Mer- 

 rimac river, and, indeed, in almost every rivulet in New England. 



" I have also noticed similar depositions between the divisional strata 

 planes of sandstones in the valley of the Connecticut, thus showing that 

 apparently the same agencies were at work during the deposition of 

 these rocks as at the present day. 



" As an example of the extent to which manganese exists in some of 

 the older rocks of New England, I submit an analysis of an altered rock, 

 occurring somewhat extensively in the neighborhood of Nahant. The 

 analysis gives, Si O 3 52,17, Fe* O 3 9,78, Mn 2 O 3 26,72, A1 2 3 8,43, 

 Ca 0, 0,37, Mg 0, 0,60, HO, 2,02 ; total 100,09." 



ON THE NEW METAL, DONARIUM. 



IN the Zircon Syenite, of Brevi^, in Norway, Bergemann has discov- 

 ered a mineral which, upon examination, proved to contain the oxide 

 of a new metal, Donarium. The mineral in question is a hydrated 

 silicate of donarium ; and is represented by the formulae. Do- O 3 Si O 3 

 -j- 2 HO. It is readily decomposed by chlorohydric acid; and, after 

 the separation of the silica in the usual manner, ammonia precipitates 

 from the solution a hydrated oxide of donarium as a white voluminous 

 mass, which, upon drying, becomes gradually yellowish and reddish 

 yellow. The precipitate contains a little iron, from which it is freed 

 by ignition and digestion with chlorohydric acid, which dissolves the 

 iron. The oxide may then be dissolved by long digestion with sulphuric 

 acid. From the sulphate the pure hydrate is obtained by precipitation 

 with ammonia white, but becoming yellowish on drying. It is readily 

 soluble in acids ; in chlorohydric acid without evolution of chlorine. 

 Metallic donarium was obtained from the oxide by heating with potas- 

 sium . The decomposition takes place rapidly with evolution of light ; 

 and the metal is separated as a coal-black heavy powder, which, under 

 the burnisher, assumes a metallic lustre, which it retains for several 

 hours, even in moist air. Particles of the metal, scattered in the flame 

 of a lamp, burn with a reddish light to oxide. Chlorohydric acid, hot 

 or cold, has no action on the metal ; nitric acid acts slowly on heating ; 

 nitro-muriatic acid oxidizes it rapidly to red oxide, of which a small 

 portion is dissolved. The anhydrous oxide, obtained by strong ignition 



