On Draining. 
267 
H umber, called Sunk Island. When first examining this soil for 
drainage, I was struck with the astonishing number of fine vertical 
holes penetrating the warp to its full depth in some places 8 to 10 
feet. These holes were evidently not the work of earth-worms, 
being of a mucli smaller bore, and worms abound in that soil, and 
were at work in their own fashion, though no other living creature 
was discernible. Very many of these minute holes seem to be fully 
appropriated by the fine roots of plants, which descend into them, 
and thus find easy access to moisture and air. 
On further investigating into the origin of this net-work of 
holes, it was traceable beyond a doubt to the existence and activity 
of myriads of small marine animals, having numerous legs, and 
minute eel-like looking fish working in the mud of recent depo- 
sition. The tidal stream from the H umber which is conducted 
upon the warping grounds, and let out again with a retiring tide 
after the deposition of its solid matter, does not destroy the life 
of these creatures, nor close their cylindrical habitations. On the 
retirement of the water they are to be seen ceaselessly occupied 
in working up and down their holes further to maintain and 
elaborate them against the next invasion. The death of these 
amphibious animals no doubt occurs when the process of warping 
terminates, and the soil solidifies, but their holes remain entire 
and open from the top to the bottom of the mass, serving to admit 
air and moisture, and to pass the water of rain in finely divided 
streamlets to the drains, and the earth-worm finally establishes 
himself in a soil easily penetrated and most congenial to his 
mining habits. In the field of warp first begun to be drained on 
this estate, I have set out the drains at about 50 feet asunder, 
their depth varying from 4 to 6 feet, as outfall permits ; but it is 
probable, as experience is gained of the draining faculty, that we 
may see fit to diminish the number of drains, and so increase 
their distance from each other in these soils. The alumina of 
the Humber warp is very fine and very retentive of moisture. 
Water appeared at 18 inches below the surface after a month of 
powerful evaporation and drought in May and June of this year, 
and copious streams were discharged from the deep drains. In 
its original state of wetness, but under circumstances of drought, 
this soil cracks widely and deeply like the stifFer clays, so that it 
seems to possess every facility for the most complete drainage, 
whilst its faculty for absorbing moisture from the air, and by 
capillary attraction from below, are of the highest order, which 
must vastly aid in conferring upon it the fertility well known to 
attach to warp lands. 
But the quality of warp varies greatly, according as the deposit 
takes place in different parts of the same stream, and at greater 
or less distance from the warping river's mouth. I cannot per- 
