There appear to be very important questions connected with the consideration of the site of the place of burial to populous districts. § 140. The question of the distance of places of burial (irrespective of convenience of conveyance) appears to be dependent on the numbers buried,—on the composition and preparation of the ground,—on the elevation or depression of the place of burial,—and its exposure to the atmosphere and the direction of the prevalent winds for the avoidance of habitations. § 141. The extent of burial ground requisite for any district will be determined by the rate of decomposition. § 142. At Franckfort and Munich, and in the other new cemeteries on the continent, where qualified persons have paid attention to the subject, the general rule is not to allow more than one body in a grave. The grounds for this rule are,—that, when only one body is deposited in a grave, the decomposition proceeds regularly,—the emanations are more diluted and less noxious than when the mass of remains is greater; and also that the inconvenience of opening the graves, of allowing escapes of miasma, and the indecency of disturbing the remains for new interments, is thereby avoided; and in the case of exhumations, the confusion and danger of mistaking the particular body is prevented. § 143. The progress of the decay of the body is various, according to the nature of the soil and the surrounding agencies. Clayey soils are antiseptic; they retain the gases, as explained by Mr. Leigh; they exclude the external atmosphere, and are also liable to the inconvenience of becoming deeply fissured in hot weather and then allowing the escape of the emanations which have been retained in a highly concentrated state. Loamy, ferruginous, and aluminous soils, moor earth, and bog, are unfavourable to decomposition; sandy, marly, and calcareous soils are favourable to it. Water, at a low temperature, has the tendency, as already explained, to promote only a languid decomposition, which sometimes produces adipocire in bodies: a high and dry temperature tends to produce the consistency and permanency of mummies. A temperature of from 65 degrees Fahrenheit and upwards, and a moist atmosphere, is the most favourable to decomposition. The remains of the young decompose more rapidly than those of the old, females than males, the fat than the lean. The remains of children decompose very rapidly. On opening the graves of children at a period of six or seven years, the bodies have been found decomposed, not even the bones remaining, whilst the bodies of the adults were but little affected. The process of decomposition is also affected by the disease by which the death was occasioned. The process is delayed by the make of some sorts of coffins. The extreme variations of the process under such circumstances as those above recited is from a few months to 30 years or half a century. Bones often last for centuries.