30 Soil. 



occasionally, for a part of the year, or constantly, may be 

 suited to grow different species of useful plants. 



8. Loam. Where a soil is moderately cohesive, less 

 tenacious than clay, and more so than sand, it is known by 

 the name of loam ("). From its frequency, there is reason to 

 suppose that, in some cases, it might be called an original 

 soil. At the same time, a constant course of tillage for 

 ages, the application of fertilizing manures, and where ne- 

 cessary, the admixture of any particular substance in which 

 the soil is deficient, (as clay with sand, or sand where clay 

 predominates), will produce a species of loam ( I0 ). 



Loams are the most desirable of all soils to occupy. 

 They are friable; can in general be cultivated at almost 

 any season of the year ; are ploughed with greater facility, 

 and less strength than clay ; bear better the vicissitudes of 

 the seasons ; and seldom require any change in the rotation 

 adopted. Above all, they are peculiarly well adapted for 

 the convertible husbandry ; for they can be changed, not 

 only without injury, but generally with benefit, from grass 

 to tillage, and from tillage to grass. They should not, 

 however, be kept in tillage too long, nor, while they are 

 in cultivation, should two white crops be taken in succes- 

 sion. 



Loams are of various sorts: 1. Sandy; 2. Gravelly; 

 3. Clayey ; 4. Calcareous ; 5. Peaty ; and 6. That mixture 

 of soil known under the name of a Hazel loam. 



1. A sandy soil is easily distinguished from a sandy loam ( 1 c ' ). 

 The former is always loose and crumbling, having no adhe- 

 sion, either when it is wet or dry. But sandy loams, having 

 a portion of clay or earthy matter mixed with the sand, be- 

 come more adhesive than pure sand ; and though they do 

 not, like clay or loam, become so cloddy as to require to 

 be reduced by machinery, yet they adhere so much, as to 

 form a proper seed-mould under the harrow. 



A mellow, rich, crumbling, sandy loam, adhesive enough 

 to fear no drought, and friable enough to strain off super- 

 fluous moisture, if incumbent on a sound subsoil, is pecu- 

 liarly profitable, being managed with much less expense than 

 any other soil, and raising, with advantage, every species of 

 crop that the climate will admit of ( Ioa ). 



2. Gravelly loams, when warm, sound, and dry, or free 

 from springs, are useful soils, more especially in wet seasons 

 and climates. 



3. A clayey or stiff loam, or brick earth, however poor 

 and cold in its original state, if it be well drained according 

 to the Essex system, occasionally fallowed, and highly ma- 



