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" liming one sort of soil and not liming another sort, for 
*' planting or sowing thinly rather than closely, and in short 
" for all the various processes and operations, must be pro- 
" nounced to know little more than half his own business. 
" I think, therefore, (says he) no more important subject 
" can occupy the attention of the agriculturist, than an 
" inquiry into the reasons why the chief processes of agri- 
" culture are more successful in some circumstances than 
" in others ; for if these reasons are once discovered, and 
" the facts connected with them established beyond con- 
" trover sy, like many of the facts in practical chemistry and 
" practical mechanics, then the farmer will have a sure guide 
in his operations, and will be as superior to the old farmer 
" of hap-hazard experience, as the modern mariner with his 
" compass is to the mariner of olden time, who dared not 
" advance out of sig-ht of land, for fear of losing- himself in 
the pathless ocean." 
In order, however, to discover the reasons why one mode 
of agriculture is better than another, it will be necessary to 
ascertain the difference of the circumstances under which 
these operations are performed, or to apply acknowledged 
principles to local circumstances; for, on a comparison of several 
modes of farming, it may be found that each has been made 
under a diversity of soils, subsoils, climate, manures applied, 
and crops produced ; so that it becomes requisite to study 
the agriculture of particular districts in relation to these 
phenomena; or, in other words, to apply to the investigation 
of the subject the cognate sciences of Geology, Chemistry, 
and Physiological Botany. 
In the last year a sub-committee of the Yorkshire Agri- 
cultural Society was appointed to obtain an essay on the 
Agricultural Geology of some part of Yorkshire, which 
should contain observations upon — 1. The geographical limits 
of the geological formation. 2. Its general character, such as 
