96 



Geology of the Keythorpe Estate, 



and approved places either by the side of, or in the place of, the 

 customs of our ancestors, we are sensibly impressed with one 

 important fact — that these very signs which herald the approach 

 of a yet more economical system of agriculture, and proclaim 

 the firm, steady march of improvement upon improvement, warn 

 us that those who do not vigilantly watch the advent of each 

 new-born pledge which the prolific union between science and 

 practice will assuredly give birth to, must inevitably be passed 

 by, and left behind in some obscure by-roads to waste their 

 remaining days in lamenting the loss of the bold independence 

 of their forefathers, and in bidding sad farewells to that material 

 prosperity which flourishes around them, but is no longer 

 within their reach. 



VII. — Notes on the Geology of the Keythorpe Estate, and its 

 relations to the Keythorpe System of Draining. By Joshua 

 Trimmer, F.G.S. 



In various communications to the Royal A gricultural Society and 

 the Geological Society, 1 have insisted on the following points : — 



1. The important influence exercised by the superficial de- 

 posits on the distribution of soils, 



2. The division of those deposits into erratic tertiaries, or 

 northern drift, and warp-drift. 



3. The division of the erratic tertiaries again into upper and 

 lower erratics : the lower erratics consisting of boulder clay, 

 possessing peculiar characters found in no other marine strata ; 

 the upper erratics composed of rolled gravel and sand, approach- 

 ing more the characters of ordinary tertiary strata, but dis- 

 tinguished from them by certain marked peculiarities. 



4. The distinctness of the warp-drift — a deposit which 

 generally forms the surface-soil, — and its subsequent origin to 

 that of the erratic tertiaries ; its presence in those districts 

 where the erratic tertiaries are absent, and its diffusion over 

 their denuded surface where they are present. 



5. The indented surface of the beds, whether of the erratic 

 tertiaries or of the older strata, on which the warp-drift rests, 

 presenting a series of irregular ridges and furrows. 



6. I suggested that the contradictory statements which abound 

 respecting the superior efficacy of deep or shallow drains, of 

 drains at wide or narrow intervals, of drains following the fall of 

 the ground, or crossing it, might, perhaps, in many cases be 

 reconciled by observing whether the drains were parallel or 

 transverse to these natural furrows and ridges. 



In corroboration of these views I referred to a statement made 



