Rudimentary Treatise on the Drainage of Districts and Lands |
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Common terms and phrases
acre admitted adopted agricultural Ancholme applicable arrangement Artesian artificial ascer average Cambridgeshire capillary action carbonic acid catch-water drains chalk channels clay consists constructed Cornish engine cost cubic cylinder Deanston deep deposit depth of drains diameter discharge distance district Ditto drainage water duct earth effect engine equal evaporation expense experiments fall feet filled filtering filtration formed furrow gallons gravel height Holmfield inches iron irrigation laid lake land layer Leeghwater less lime loose stones lower main drains materials minor drains moisture natural open drains particles passage pipe piston plough pores porous proportion pump purpose quantity of rain quicklime raised reservoir revolutions per minute ridges river river Ancholme river Nar River Trent rood sand shown in fig side sluices soil space spade springs steam stone drains strata stratum subsoil supply surface tion tubes vegetable water-meadows water-wheel wheel width yards
Popular passages
Page 23 - ... whereas all the larger pores — those between the particles of soil — communicate most freely with each other, so that they form canals ; the small pores, however freely they may communicate with one another in the interior of the particle in which they occur, have no direct connection with the pores of the surrounding particles. Let us now, therefore, trace the effect of this arrangement.
Page 22 - ... down to the finest powder; and, on account of their " extreme irregularity of shape, they cannot lie so close to " one another as to prevent there being passages between " them, owing to which circumstance soil in the mass is " always more or less porous. If, however, we proceed to " examine one of the smallest particles of which soil is " made up, we shall find that even this is not always solid, " but is much more frequently porous, like soil in the mass. " A considerable proportion of this...
Page 24 - Let us observe still another condition of soil ; in this instance, as far as water is concerned, the soil -is in its healthy condition — it is moist but not wet, the pores alone being filled with water. But where are the canals ? We see them in a few places, but in by far the greater part of the soil none are to be perceived ; this is owing to the particles of soil having adhered together, and thus so far obliterated the interstitial canals that they appear only like pores. This is the state of...
Page 26 - Of course, all these injurious effects are at once overcome by thorough-draining, the result of which is, to establish a direct communication between the interstitial canals and the drains, by which means it follows, that no water can remain any length of time in these canals without, by its gravitation, finding its way into the drains.
Page 47 - To understand the nature of the process, it will be necessary to advert, in a general way, to a few long-known chemical properties of the familiar substance chalk ; for chalk at once forms the bulk of the chemical impurity that the process will separate from water, and is the material whence the ingredient for effecting the separation will be obtained. " In water, chalk is almost, or altogether insoluble ; but it may be rendered soluble, by either of two processes of a very opposite kind. When burned,...
Page 10 - ... a precipitation ensues. If the masses are under saturation, then less precipitation takes place, or none at all, according to the degree. Also the warmer the air, the greater is the quantity of vapour precipitated in like circumstances...
Page 25 - Not only are the pores filled, but the interstitial canals are likewise full, and the consequence is that the whole process of the germination and growth of vegetables is materially interfered with. We shall here...
Page 27 - ... of the whole bulk of the soil itself; for example, 100 cubic inches of moist soil (that is, of soil in which the pores are filled with water, while the canals are filled with air), contain no less than 25 cubic inches of air. According to this calculation, in a field pulverized...
Page 22 - The most careful examination has proved that the process of germination consists essentially of various chemical changes, which require for their development the presence of air, moisture, and a certain degree of warmth. Now it is obviously unnecessary for our present purpose that we should have the least idea of the nature of these processes : all we require to do, is to ascertain the conditions under which they take place ; having detected these, we know at once what is required to make a seed...
Page 84 - ... an acre. This increase in value has arisen, not only from the land being cleared from the injurious effects of the water upon it, but from the improved system of cultivation it has enabled the farmers to adopt. The fen-lands in Cambridgeshire and great part of the neighbouring counties are formed of a rich black earth, consisting of decomposed vegetable matter, generally from 6...