AGRICULTURAL MUSEUM 3o9 



calcareous [nq^rcdient or ciialk miicli predominates. It 

 is L'ss cohesive than claj ey Iop.dis. 



. Sandy Ijoam denotes a loam io wlii^h sand nr'^domf- 

 natcs — it is less coliercnt than either 0^1!;.; ab.rre nion- 

 tioned. Sand partly coarse and ;)artlj- ilne, forms from 

 80 to 90 per cent of Ih.is coinpouiul. 



Cravelly Loam differs i'rom the last ordy in conta'n- 

 in<j a lai'oer mixture of coarse sand or pelibles. Tl^is 

 and die two last, aic genera!!}' caiied by farmers, li^jht 

 or hungry soils, particuhirl}' when they have bat liUic 

 depd) — They arc propcrlv so called when the cli-dk, 

 sand or gravel preponderates too much, so that it vvdl 

 not retain a suuiciency of moisture, not otherwise ; for 

 gravelly loams and sandy lonms are often found very 

 fertile and durable ; for instance, the best tobacco lands 

 in Maryland. 



Fcrrnginons loam, or till. Th Is is generally of a dark 

 brown, or reddish colour, and much harder tlian any of 

 tlie preceding. It consists.of clay aiidealces of iron more 

 or less iniimately mixed. It may be distinguished not 

 only by its colour, but also by its suj-erior weight; it 

 sometimes effervesces with acid?, and sometimes not ; 

 when it does, niueh of the iron\' part may be separated 

 by pouring it, when well dried, into spirit of salt, from 

 which the iron may aiterwiuds be separated by alkal^ 

 or chalk — akin to this are certain vitriolic soils, which 

 when steeped in water, impart to it the power of red- 

 dening syrups of violets. Tliesc are generally of a blue 

 colour, but redden when heated. 



Boggi/. Soil or Ijoggs, consist chiefly of ligneous 

 roots and decayed vegetables mixed uith cai th, most- 

 ly rrgillaceous, and sand and u coaly substance, deri- 

 ved irom decayed vegclablos. 



Of Boggs tiiere are two sorts, ihc black, which con* 

 tains a large propoiticn of clay, and of roots njore per- 

 fettiy decayed, with mineral oil. In the red, the roots 

 seem less perfectly decayed, and to k>'. m a princnpal 

 part, S\LVANU5, 



[ To be conlinned.] 



