978 Museum of Economic Geology of Lidia. [No. 106. 



so that by careful analysis of the whole, with due attention to climate 

 and the other obvious conditions to which they may have been ex- 

 posed, some general and useful results may be brought to light, respect- 

 ing the soils best fitted for the growth of the various plants usually 

 cultivated in this country. 



In selecting soils for the Museum of Economic Geology, care should 

 be taken to obtain fair average specimens of the localities whence it 

 may be considered desirable to send them ; and to insure the true sub- 

 soil, subjacent hard rock, clay, sands, &c. ; specimens of the latter should 

 be obtained as near as possible beneath the spot whence the soil may 

 have been so selected, for it sometimes happens, that the soil of a field 

 varies in places, from resting upon different kinds of sub- soils. 



The soil above hard rocks is not unfrequently separated from them 

 by broken angular fragments, the half- decomposed portions of such hard 

 rocks ; specimens therefore of sub-soils, or subjacent mineral substan- 

 ces should, in such cases, be taken from the solid hard rocks beneath, 

 and not from these fragments, which have commonly suffered too much 

 decomposition to exhibit the real chemical composition of the rocks 

 themselves. These angular fragments must not be confounded with 

 gravels, sometimes overspreading hard rocks, to the depth of several feet, 

 and chiefly or wholly composed of rounded pebbles, mixed with earthy, 

 sandy, or clayey matter, the whole being often derived from a distance ; 

 for such gravels then form the true sub- soil, and the soil above them 

 would partake of the character of the earth, sand, or clay, mixed with 

 the pebbles, with the addition of the decomposed parts of such of the 

 latter, as may disintegrate by the effects of the weather upon them. 



The quantity of soil taken as a specimen, should weigh about a 

 pound ; it should be well dried and tied up in a canvass bag, labelled 

 to correspond with a memorandum, in which the general agricultural 

 produce of the spot, whence the specimen was taken, should be noted ; 

 the kinds of manure known to have been used upon it mentioned ; 

 the amount of grain or other crops per beegah stated ; the dimensions 

 of the beegah, and the best kind of produce which has been hitherto 

 obtained from it, specified. A loose label should also be inclosed 

 within the bag to guard against accidents. As so much depends on 

 climate and position, the general character of the seasons should be 

 pointed out, and the aspect of the ground, as regards exposure to \ 





