The soil is rapidly dried to arrest nitrification; it is not heated above 40° lest there should be dissipation of ammonia compounds, or a change in solubility. The normal limit to which the soil may be heated in place by the sun’s rays should not be exceeded in preparing a sample for an agricultural chemical analysis. The relative amount of fragments too coarse to pass through the sieve should be made a matter of record. They are soil material, but not yet soil, so far as agricultural purposes are concerned. =71. Method of Lawes.=—In a late method of sampling proposed by Sir J. B. Lawes[55] a steel frame ten by twelve inches, and nine inches deep open at top and bottom is driven into the earth until its upper edge is level with the surface of the soil. All above-ground vegetation is then cut off as closely as possible with scissors. The soil within the frame is then removed exactly to the depth of the frame, and immediately weighed. It is then partially dried, and mechanically separated by a series of sieves, all visible vegetable matter being at the same time picked out. The stones and roots and the remaining soil are thus separated, and the determinations of dry matter, nitrogen, etc., are made in the separated soil after being finely powdered. The loss of water at each stage of preparation and on drying the samples as analyzed is also carefully determined. This method, which requires the soil to be taken to an arbitrary depth of nine inches, could not be used when samples of strictly arable soil are to be taken. =72. In taking= a sample by the French commission[56] method it is necessary to remove from the surface, the living and dead vegetation which covers the soil. With a spade a square hole is then dug to the depth of about 500 millimeters; in other words, to a depth considerably exceeding that of the arable layer. Afterwards on each of the four sides of the hole there is removed by the spade, a prismatic layer of the arable portion of a thickness equal to its depth. The samples thus obtained are united together and carefully mixed for the purpose of forming a sample for analysis. If there are large stones they are removed by hand and their proportion by weight determined.