Ehrenberg and Hausmann on Siliceous Earth. 375 

 ditional extension, and demonstrate that these three agents 

 which rule in the atomic constitution of bodies, are derived, ac- 

 cording to all appearances, from a single principle of an ethereal 

 nature, spread throughout space and through all bodies. 



On Profeasor Ehrenberg and Hausmann' s Discoveries regard- 

 ing two varieties of Siliceous Earth found near Oherohe in 

 the Hanoverian Province of Liineberg. 



On the 8th January 1838, Professor Hausmann communi- 

 cated to the Royal Society of Sciences of Gottingen, a prelimi- 

 nary notice, on a discovery connected with our own country, 

 which is undoubtedly among the most remarkable facts lately 

 added to the science of geognosy. 



In the month of November this year, Colonel von Hammer- 

 stein, President of the Provincial Agricultural Society at 

 Uelzen, in the territory of Liineberg, the able author of seve- 

 ral prize essays, and the zealous promoter of the agriculture 

 of his native country, had the goodness to send to Professor 

 Hausmann two specimens of varieties of earth, which were 

 dug out near Oberohe during an excavation made by the 

 above-mentioned society in the district of Ebstorf. The ex- 

 treme lightness of these varieties of earth rendered it improba- 

 ble that they were of an argillaceous nature ; but their state of 

 aggregation did not permit us to conclude that they consisted 

 of pure silica, although, notwithstanding this, they really have 

 such a composition, according to the chemical examination 

 kindly instituted by Dr Wigners in the academical laboratory. 

 The specimen No. 1. according to this investigation, is chemi- 

 cally pure silica. It has, at the same time, a fine, extremely 

 loose, earthy, flaky consistence, and a chalk- white colour. It 

 has a soft and meagre feeling, somewhat like starch, and does 

 not grate between the teeth. On water it swims for a moment, 

 then sinks down, and gradually swells up. Mixed with a little 

 water, it acquires a pasty consistence, without being adhesive. 

 The specimen No. 2 is also silica, but contains likewise a very 

 insignificant quantity of a matter destructible in fire. Its frac- 

 ture is fine-earthy ; the colour brownish-grey, slightly inclining 

 to green, becoming darker by the addition of moisture. It is 



