On Thorough- Draininy. 
35 
a tender crumbling substance, called by the labourers hurrick 
which will not stand longer than the thorns last, and which soon 
spoils the drains — perhaps in ten or twelve years. In such cases 
it is usual to cut a few fresh drains across the old ones, which 
bleed them, and lay the land dry for some years longer. 
G. Efficiennj. — They are so efficient as completely to effect the 
object desired ; and are considered, in most cases, to return the 
outlay in the first two or three crops. I should say the benefit is 
greatest on those soils that have a tolerably good depth of staple 
or useful soil. On the thin clays, though quite as necessary, the 
immediate improvement is not so apparent. Without draining, 
however, these could not be cultivated to any advantage ; and 
here are never attempted to be so cultivated, if the occupier has 
the means to drain. 
By means of improved machinery drain- tiles are now much re- 
duced in price ; but, after much attention to the subject, I prefer 
the thorn-drains, as much of our clay is of so tenacious a texture 
that I think it would soon become so consolidated over the tiles as 
to prevent the water reaching them, unless they were filled over 
the tiles with broken stones, or some porous material, which 
would very greatly increase the expense. 
I remain. Sir, 
Your obedient servant, 
W. Flack. 
fVaters Place ^ Ware, January 11, 1843. 
III. Essex Draining — 1. By Robert Baker. 
[7%is and the two following statements were oblaitied for the Society by Mr. Bramslon.] 
Under-draining has been long practised in Essex : the commence- 
ment of the system I have no opportunity of ascertaining ; but from 
observations that I have heard made by others, I believe it was prevalent 
through all that portion of the county where the white chalk clay 
abounds — taking in nearly all that portion lying north of the line ex- 
tending from Great Tey to Chelmsford, and from the latter place to 
High Ongar and Epping. 
The Toothings and parishes around Dunmow have been most remark- 
able for its being carried out extensively ; it has at a later period been 
introduced upon the mixed and gravelly subsoils, consisting of chalk, 
loam, and clay, mixed in different proportions. 
The chalk-clay is a deposit resting upon the London clay, and varies 
in thickness from 10 to 100 feet. As it approaches Cambridgeshire it 
becomes mixed with a larger proportion of chalk, and at Saffron Walden 
is superseded by the chalk which extends northward through that 
county. This soil is peculiarly adapted to draining, and produces ex- 
cellent wheat and barley crops in alternate years under the system. The 
