126 On the Tchornoi Zem, 



of Russia. The object, in the mean time, of this short notice is 

 to call attention to a superficial deposit which occurs at intervals 

 over enormous tracts in central and eastern Russia, and which, 

 from the uniformity of its colour and composition, is without 

 parallel in Europe. Though Pallas and the older writers upon 

 Russia have briefly noticed the occurrence of a black vegetable 

 mould, they have neither described the extent of ground occupied 

 by it, nor its composition ; still less have they speculated upon 

 its probable origin. The Baron A. Von Meyendorf, my com- 

 panion in a part of my first journey, in a letter to M. Elie de 

 -Beaumont, has indeed spoken of this material as being one of the 

 chief sources of the agricultural wealth of the empire. 



Having recently, however, had the opportunity, in company 

 with M. de Verneuil and Count A. Keyserling, of tracing the 

 relations of this black earth over wider tracts than perhaps any 

 modern observer, I have thrown together a few remarks which 

 may serve to explain, 1st, the range and extent of the deposit, and 

 its relations to the physical features of the land ; 2ndly, its agri- 

 cultural properties; 3rdly, its chemical composition; 4thly, the 

 theory of its origin. 



1 . The black earth has its northernmost limit defined by a waving 

 line which, passing from near Kief and Tchernigof, a little to the 

 south of Lichwin, appears in the 54° of N. lat. in that tract, then 

 advances in its course eastward to the 57° of N. lat. and occupies 

 the left bank of the Volga west of Tcheboksar, between Nijny 

 Novogorod and Kasan. In approaching the Ural chain, we saw 

 no black earth to the north of Kasan, but we observed it plentifully 

 on the Kama and around Ufa. Again, on the Asiatic or Siberian 

 side of the Ural mountains we travelled through one large oasis 

 of it near Kamensk, south of the Issetz river in latitude 56° N., 

 and through another, between Miask and Sviask. Of its limits 

 in the great Siberian plains we cannot speak from personal 

 observation, but v/e were given to understand that it spreads 

 over a considerable area in the eastern and central parts of that 

 region. Nor can we exactly define its southern limits in these 

 eastern longitudes, for although we met with it occasionally in 

 the gorges of the chain and in the Baschkir country on both 

 flanks of the southern Ural, and also in the steppes of the 

 Kirghis, \Ye cannot pretend to say if it extends far to the south 

 of Orenburg. We know, however, that it is not to be seen 

 in the flat southern steppes between that place and the mouth 

 of the Volga which were traversed by us ; for there the sur- 

 face is strewed with fine submarine detritus containing nume- 

 rous shells of the same species as those which now inhabit the 

 adjacent Caspian. Nor have we seen any black earth to the 

 south of Tzaritzin on the Volga, or on the steppes of the Kal- 



