CLAY SOILS. 



and assert tliat, instead of three 

 crops in four years, which is the com- 

 ITion method, and an improvement on 

 the old system of two crops and a 

 fallow, five might easily be obtained, 

 especially if clovers are considered 

 as crops. For example: 1. Oats or 

 barley ; 2. Clover ; 3. Wheat ; 4. Tri- 

 folium cut in May, and succeeded by 

 spring rye, cabbages, or potatoes. At 

 all events, the trifolium or winter rye 

 may always be had in the year in 

 which the land is to be cleaned by 

 repeated ploughings, as they may be 

 cut early in summer, and leave ample 

 time for the operations. [ 



The most profitable management 

 of a stiff, wet clay soil, after thorough 

 draining it, is to cultivate it on the 

 convertible system, that is, to have 

 it three years in grass and three 

 years under the plough, unless a per- 

 manent and good sward can be ob- 

 tained upon it, in which case it will 

 give the surest return by remaining 

 iu grass. A preliminary course of 

 croppii:::, with ample manuring, will 

 so much improve the texture of the 

 surface that a much better herbage 

 will grow upon it ; and when this is 

 well established, it may be left so 

 until it degenerates. 



The effect of burned clay as a ma- 

 nure has been highly extolled, and 

 not without some reason in particular 

 situations. Clay by burning alters its 

 nature : it becomes insoluble in wa- ', 

 ter, and loses its attraction for it ; it 

 then resembles silicious sand, and 

 may greatly improve a verj' strong, ' 

 retentive clay, tempering it and ren- 

 dering it more porous. To burn clay, 

 it is dug out in lumps and dried ; 

 heaps are made of these at regular I 

 distances in a field, with a small cav- 

 ity in the centre, into which dry brush- 

 wood is introduced. This being light- ! 

 ed, the lire is allowed to burn very ' 

 slowly, and the smoke ke[)t in by add- 

 ing a sod wherever it bursts out. \ 

 Wh?n the heap is once burning, more 

 clay may be added, even without be- 

 ing dry, and the combustion goes on | 

 without other fuel. It mu.st be so i 

 managed as to bake the clay without 

 oeating it too much ; and when the i 



heaps are cooled and opened, the 

 whole should appear pulverized, and 

 of a red colour if oxide of iron exists 

 in the soil. A coat two or three inch- 

 es thick spread over a field, and 

 ploughed in, will greatly improve its 

 texture ; but sufficient animal or ve- 

 getable manure must be added to 

 make it fertile. 



An improved method of burning 

 clay has been adopted in Northum- 

 berland. Instead of building a kiln, 

 gratings or arches of cast iron are 

 used to form a vault or funnel for the 

 fuel, and over this funnel the clay is 

 built. The grated arches are made 

 about two feet and a half long, two 

 feet diameter, and about fourteen 

 inches high. One grating is to be 

 filled with brush-wood, stubble, or 

 any other cheap fuel, and the clay, as 

 it is dug, built upon it to a convenient 

 height, leaving small vacancies, or 

 boring holes, to allow the heat to 

 penetrate to the middle arxl outer 

 parts of the clay. "When a sufficient 

 quantity is built upon the first gra- 

 ting, another is added at either end, 

 or at both, filled with similar fuel, and 

 the clay built upon them as before. 

 This process is continued until ten, 

 twelve, or a greater number of the 

 gratings have been used, when one 

 end is built up or covered with clay, 

 and at the other, under the last gra- 

 ting, a fire is made of coals or fagot- 

 wood. The end at which the fire is 

 made should face the wind if possi- 

 ble, and if the process has been prop- 

 erly conducted the clay will be effec- 

 tually burned. By commencing with 

 a centre grating in the form of a cross 

 (see Fig.), the workman may build 



ir)3 



