158 PREHISTORIC EUROPE. 



According to analyses by Phillips, Daubeny, and Payen, which 

 are given by Murchison and his eminent associates Verneuil 

 and Keyserling, 1 the black-earth is composed of siliceous sand 

 (about 70 per cent), alumina, and other mineral ingredients (23 

 per cent) and organic matter (about 7 per cent), the latter con- 

 taining nearly 2 - 5 per cent of nitrogen. A nearly similar result 

 was obtained by Hermann from three analyses, the amount of 

 organic substances being 1042 per cent. 2 Professor Goebel some 

 years before had analysed two specimens of black-earth from 

 the neighbourhood of Saratov. 3 One of these yielded 22 per 

 cent of combustible and vegetable ingredients, and the other 23 

 per cent, the former yielding 6 - 25 per cent, and the latter 14-5 

 per cent of humic acid. The other ingredients consisted chiefly 

 of silica and alumina, etc., but while one specimen contained 

 only 4'50 per cent of carbonate of lime, the other showed not 

 less than 30 - 12 per cent. Murchison and his colleagues state 

 that the black-earth is wholly unfossiliferous, not a trace of any 

 organism, either plant or animal, having been detected by them. 

 Goebel, however, states that in subjecting one of his specimens to 

 a mechanical separation he found, in one hundred parts, 9 - 7 per 

 cent of stony ingredients with "coarse organic remains," and 90 - 3 

 per cent of fine sifted earth. The other specimen contained 

 neither stony ingredients nor "coarse organic remains." Of 

 the 9 - 7 per cent of coarse-grained matter, 4*19 was made up of 

 vegetable debris, and 5 "51 of clay. Unfortunately, Goebel does 

 not tell us from what depth the specimens were taken, but it is 

 probable that they were obtained at or close to the surface : he 

 describes them indeed as being " Ackerkrume " (mould). 



According to Murchison, etc., the black-earth " occupies the 

 centre of a trough, large as an European empire, having the 

 detritus of the crystalline and older rocks for its northern, and 

 the low granite Steppes and Caspian deposits for its southern, 



1 Geology of Russia in Europe and the Ural Mountains, vol. i. p. 559. 



2 Cited by Bischoff, Elements of Chemical and Physical Geology (English, 

 edition, 1854), vol. i. p. 135. The reference there given is Journ. fur pract. 

 Chemie, Bd. xii. p. 290. 



8 Beise in die Steppen des sudlichen Russlands, 1838, Bd. i., p. 297. 



