# From G. H. Darwin   30 December 1871

Dec. 30. 71

A grass field betw. Leaves Green & the Salt Box house on the right hand of the road is marked with ridge & furrow.1 The field contains the end of a small valley where it quite dies out, so that the land is somewhat in the shape of a shallow spoon;—the furrows run parallel to the main line of the small valley ie parallel to the handle of the spoon.— Horace2 & I attempted to find the depth of the soil above the flints in the steepest part where the furrows ran transversly to the hill by probing with a stick   I probed in the furrows & he on the ridges about 10 or 15 times each & then I found that the average distances of the flints below the surface on the furrows & ridges were about 5 inches & 3$\frac{1}{2}$ inches respectively. We excluded the cases in wh. the stick obviously missed the flints & went in deep.— We tried the same thing in a part of the field which was nearly flat & found the depth below the furrows & ridges to be about 4 inches & 3$\frac{1}{2}$ inches respectively.— The furrows appeared slightly more filled up on the hill side than on the flat   There were a good many earth castings about tho’ I shd. say that they were by no means very numerous

G H D

## Footnotes

Leaves Green is near Biggin Hill, Keston, in Kent, and is less than two miles from Down House.
George’s brother, Horace Darwin.

## Summary

Varying depth of top-soil in a ridge-and-furrow field with a depression.

## Letter details

Letter no.
DCP-LETT-8124
From
Darwin, G. H.
To
Darwin, C. R.
Sent from
unstated
Source of text
DAR 162: 64
Physical description
AmemS 3pp

## Please cite as

Darwin Correspondence Project, “Letter no. 8124,” accessed on 24 January 2017, http://www.darwinproject.ac.uk/DCP-LETT-8124

letter