RELATION OF THE CULTURES 651 



of growth of the sediments in aggrading the delta on the one hand and 

 of the culture strata on the other. 



By referring to the annexed profiles through the south kurgan yon 

 will see that a low plateau extends out from the main and high part of 

 the kurgan. Now, while shaft C, sunk to the bottom through the heart 

 of the high part, passes uninterruptedly through culture strata, shaft D, 

 in the projecting plateau, after sinking through culture strata, enters 

 natural sediments, below which it passes again through culture strata till 

 it finds the base of culture at the same level as under the main body of 

 the kurgan in shaft C. 



As we recognize geological horizons by their characteristic fossils, so 

 here we recognize the cultures to which these strata belong by the very 

 characteristic pottery in which they abound. We find interbedded in the 

 natural sediments in shafts E and F a layer of wash containing frag- 

 ments from the same lower culture that was cut in shaft D. After the 

 deposition of this pottery the natural sediments grew 19 feet in height, 

 submerging the settlement and rising to the level at which it is covered 

 by culture strata in shaft D, which is 16 feet below the beginning of the 

 pure iron culture. 



Now, the evidence in shaft C is that the main body of the kurgan grew 

 uninterruptedly from its base 52 feet, to reach there the level, 16 feet 

 below pure iron culture. If we assume that these 19 feet of sediments 

 began to grow contemporaneously with the founding of the kurgan, the 

 relative rates of growth would be 52/19 = 1 : 2.733. 



It is possible, however, that the whole thickness of the 7 feet of sub- 

 merged culture strata contributed to the layer of "wash" with pottery in 

 shafts E and F; therefore, if we subtract these lowest 7 feet of culture 

 strata shown in shaft D from the 52 feet in the main body of the kurgan, 

 we have the rates: 45/19 = 2.368; say, 2.37. But, everything consid- 

 ered, it would seem proper to take 1:2.5; that is, 1 natural sediments 

 to 2.5 culture strata as the relative rates of growth. 



This ratio being obtained from the parallel accumulations of a con- 

 siderable period of time has, as we shall see later, for our purpose both 

 an archeological and geological value. 



After the sediments had reached the height shown in shaft D, there 

 came a change, and this part of the plain was dissected; for, a little 

 farther eastward in shaft B, we find a new series of sediments marking 

 a renewed aggrading. 



Now, when this new growth had reached the level indicated by a dot 

 below the letter P, in shaft B, it received fragments of the pottery pecu- 



