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accumulated acetic acid acid action of worms alimentary canal amount angle animals annelids apex appeared basal base Beaulieu Abbey beneath the surface blown brought buried burrows carbonic acid castings ejected cent chalk close concrete covered damp depth disintegration doubt dragged drawn earth feet field flints floor formed fragments fresh castings gizzards glands grass grass-covered ground heavy rain Hensen holes inches beneath inches deep inches in thickness intestines Knole Park land large number ledges Leith Hill Place lime Maer Hall manner matter mortar mouths nearly neath objects observed overlying particles pasture pavement penetrated Perrier petioles pharynx places ploughed plugging pots probably Roman villa rubbish sand seen seized side Silchester slope soil square yard Stonehenge stones subsided swallowed tesselated tesserae thrown tiles tion tips trench triangles triturated turf upper vegetable mould walls washed weather weight whilst whole worm-castings worms zards
Page 316 - The plough is one of the most ancient and most valuable of man's inventions; but long before he existed the land was in fact regularly ploughed, and still continues to be ploughed, by earthworms. It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organized creatures.
Page 308 - On each acre of land, he says, "in many parts of England, a weight of more than ten tons of dry earth annually passes through their bodies and is brought to the surface.
Page 308 - They have played a more important part in the history of the world than most persons would at first suppose.
Page 137 - Two other cases are worth recording. In the spring of 1835, a field, which had long existed as poor pasture and was so swampy that it trembled slightly when stamped on, was thickly covered with red sand so that the whole surface appeared at first bright red. When holes were dug in this field after an interval of about 2.\ years, the sand formed a layer at a depth of f in.
Page 67 - ... and in this case the tips projected from the burrows; and 26 had been seized near the middle, so that these had been drawn in transversely and were much crumpled. Therefore 80 per cent (always using the nearest whole number) had been drawn in by the tip, 9 per cent by the base or footstalk, and 1 1 per cent transversely or by the middle.
Page 131 - The slow rate at which mould can increase to a great thickness — Conclusion. WE now come to the more immediate subject of this volume, namely the amount of earth, which is brought up by worms from beneath the surface, and is afterwards spread out more or less completely by the rain and wind. The amount can be judged of by two methods,— by the rate at which objects left on the surface are buried, and more accurately by weighing the quantity brought up within a given time. We will begin with the...
Page 311 - Mississippi, that its enormous drainage-area must on an average be lowered '00263 of an inch each year ; and this would suffice in four and a half million years to lower the whole drainage-area to the level of the sea-shore. So that, if a small fraction of the layer of fine earth, -2 of an inch in thickness, which is annually brought to the surface by worms, is carried away, a great result can not fail to be produced within a period which no geologist considers extremely long.
Page 145 - When they ran down the slope the stones clattered together, I remember doubting whether I should live to see these larger flints covered with vegetable mould and turf. But the smaller stones disappeared before many years had elapsed, as did every one of the larger ones after a time; so that after thirty years (1871) a horse could gallop over the compact turf from one end of the field to the other, and not strike a single stone with his shoes.
Page 141 - ... stiff red clay, full of flints, and generally from 6 to 14 feet in thickness. Over the red clay, wherever the land has long remained as pasture, there is a layer a few inches in thickness, of dark-coloured vegetable mould. A quantity of broken chalk was spread, on December 20, 1842, over a part of a field near my house, which had existed as pasture certainly for 30, probably for twice or thrice as many years. The chalk was laid on the land for the sake of observing at some future period to what...