556 W. F. Hume— Notes on Russian Geology. 



" wilderness blossoms and rejoices like the rose." Indeed, it but 

 adds another to the numerous examples of contrast which so con- 

 stantly occur in science, for we should scarcely expect dreary salt 

 deserts to be the spots which should subsequently become the richest 

 corn-growing districts of the world. 



Supported as the above theories are, by wealth of argument, by 

 ■wide experience, and by a vast knowledge of the literature of the 

 subject, they must ever remain as central cores round which the 

 the future development of the question shall crystallize. 



Criticisms have, however, arisen especially as regards the want 

 of stratification. Thus in the early part of this year Mons. G. Capus 

 (Comptes Rendus, April 19, 1892), argued that the greater part of 

 the Loess, especially in Turkestan, must have been formed under 

 water. He bases this view on the presence of stratification, variations 

 in composition, and the occasional presence of conglomerates, though 

 he admits that many local but small accumulations may be due to 

 wind action. 



Prof. Armachevsky has also propounded a theory for the Russian 

 Loess, based upon his observations in the Tchernigov Government. 

 He expresses himself as follows : — 



" The action of atmospheric water in sharply-rising places is 

 double. By energetic and unequal action the mass of mineral parts 

 is carried away and deposited in hollows, or fills up any inequalities. 

 By weak and regular action, waters flowing from gentle slopes as 

 small streams, expend their energies in partly wearing away the 

 irregularities which are to be found in those places, distributing their 

 materials over the places themselves. Such an action of the water 

 in sharply rising places, in connection with the fact that the Loess is 

 only found in such places, permits us to assert that the Loess owes its 

 origin to the action of such scarcely-to-be-observed, gentle streams, 

 which, flowing along the slopes from higher to lower positions, dis- 

 tribute their mineral load along the road. The following facts 

 support this view : — 



(1) The underlying stratified clays and sands containing gravel 

 show undoubted proof of the action of water. Loess is closely bound 

 with them, so that it is difficult to believe that they have different 

 origins. The sands and clays are deposits formed on dry land by 

 means of flowing water, the action of which was less regular than 

 when Loess was laid down. 



(2) Loess in a horizontal direction passes over into stratified 

 sands. 



(3) The underlying strata have undergone great denudation, 

 giving rise to inequalities and deepenings afterwards partly filled 

 ■with Loess. 



It will be seen from the above references how different are the 

 views which have been propounded on this subject. In reconsidering 

 the question, it seems advisable to ask : 1st, what was the geological 

 history of the counti'y before the Loess period, and 2ud, what was its 

 physical history afterwards, viz., at the present day. 



1st. In Eocene times the whole, or greater part of S. Russia 



