or Black Earth of Russia. 131 



which I extracted six months ago from beneath 10 to 12 feet of 

 subjacent similar earth, all jet black when moist, and which I had 

 kneaded together to bring away, it offered in its dry state a slightly 

 ferruginous brown tint ; and I further perceived that besides the 

 black matrix, grains of lighter-coloured sand were interspersed. 

 Having submitted a portion of this mass to Mr. R. Phillips, the 

 Chemist of the Museum of Economic Geology, he has obligingly 

 furnished me with this analysis: — 



Silica . . . .69-8 



Alumina . . . .13*5 



Lime . . . .1-6 



Oxide of iron . . .7 



Vegetable matter . . .6*4 



Traces of humic acid, sulphuric acid, chlorine, &c. 1 '7 



100 

 Dr. Daubeny, who has also interested himself in the examination 

 of this black erirth, and has detected about the same proportion 

 of organic matter as that noticed by Mr. Phillips, thus expresses 

 himself: — '' The possession of a deep soil, easily penetrated by 

 the roots of plants, and containing so large a per centage of mild 

 humus, would alone impart great fertility." 



The celebrated French agricultural chemist, M. Payen, who 

 analyzed a portion of this black earth at the request of M, de 

 Verneuil, says : — ■ 



" The composition of this earth is remarkable for the propor- 

 tion of azotised matter which it contains, and the volume of the 

 azote. The connection between this earth and the organic sub- 

 stance, when the latter is so rich in azote, appears to me to be 

 essentially one of the surest indications of the fertility of soil, 

 other conditions of chemical properties and mineral composition 

 being favourable. In this respect, and according to my compared 

 analyses, the earth in question approaches very near to two of the 

 most fertile soils of France, that of the Limagne d' Auvergne (valley 

 of the Upper Loire) and that of the neighbourhood of St. Denis, 

 near Paris, notably in the farms of Marville and Stains. I have 

 great pleasure in authorising Mr. Murchison to publish this 

 analysis and the opinion I here express, and shall be much ho- 

 noured if these details find a place in the Memoir of the Presi- 

 dent of the Geological Society of London." 



ANALYSTS OF THE BLACK EARTH BY M. PAYEN. 



iro f f fi"05 Combustible organic matter rAlumine 



, P^I^ { 93 • 05 Incombustible j Soluble in ] Oxide of iron 



ot earth j matter = { boiling hydro- 13-755 1 Lime . . 



[ chloric acid J ] Magnesia . . 



Alkaline \ 

 Chlorides) 



k2 



5-04 

 5-62 



• S2 

 0-98 



1-21 



