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On Kunker formations, ivith Specimens. By Captain J. Abbott, B.A. 



I have the pleasure to send you a few specimens of Kunker, collected 

 by me in my late journey down the Ganges. I had purposed bringing 

 away a small section of a Kunker formation, showing the substance 

 in which it is imbedded and the strata immediately above and beneath ; 

 but I was travelling in too great haste for this. The accompanying 

 specimens, however, exhibit nearly every species of Kunker the matrix 

 of one, and its calx after the extraction of the lime by fire. 



I have been so separated from scientific literature for many years 

 past, that I know not what may be the existing theories of the forma- 

 tion of this mineral ; and in offering the following am prepared to find 

 myself forestalled if, indeed, the theory is well founded. 



The word Kunker, in its general application, like our own term gravel, 

 is applied by the natives to any small or rounded masses of stone, 

 whatever their substance, but it includes especially every variety of the 

 limestone under consideration. This is found in several forms in the 

 wide plains of Upper and Central India. Not I think in Afghanistan 

 nor Persia, nor any where beyond the influence of the periodical rains. It 

 occurs only in mixed strata of sand and clay, which on analysis prove 

 to be impregnated with lime, and its presence is generally denoted by 

 the sterility of the soil above it. 



Its position from the surface of the soil varies from ten to fifty feet 

 or more. But although, through the erosion of the upper stratum (as 

 for instance in the neighbourhood of large rivers) it may sometimes be 

 found at the surface, it is never there formed or deposited originally. 



Its forms arc- 

 Is?. Small rounded drops, from the size of a pea to that of a bullet, 

 in a matrix of clay and sand often of great depth, but seldom separat- 

 ed into distinct homogeneous strata. 



2ndly. In distinct strata of larger masses, from the size of a small 

 potato to that of a man's foot ; with a matrix of clay, or of clay and 

 sand mixed. In such cases the clay and sand strata are generally distinct. 



Zrdly. In what is improperly termed stratified Kunker, but which I 

 take the liberty to name confluent Kunker, (almost all Kunker occurring 

 in strata.) In this form it presents extensive fields, from one to five 

 feet in thickness, generally very rugged and porous, but occasionally se- 

 parable into compact masses of a hundred solid feet or more. 



