414 Cil ttictiilon itffc?7v7/i Land- 77 dtcrcd *ft8th &t //&amp;lt; 



-TAJ- v I 



:;Tilbrding advantage in the way of depofition. It is only in the time of floods that 

 they can produce much utility in this way at any great diftance. It was found by 

 an able philosophical writer, that the water of the Darwent, though it flows for 

 fbvcral miles, near Matlock, through calcareous ftrata, contained no impregnation 

 df this fort on its reaching Derby, although the fprings in that neighbourhood had 

 a large proportion of it in their compofition.* 



The fame author has ingenioufly fuggcftcd another mode in which water may 

 prove fcrviccablc in floating grounds in this climate, which is that of protecting 

 the grafs or other plants from the too fevere effects of cold during the winter or 

 early fpring feafon. In this view it is obferved, that the water of flrong fprings, 

 M Kirch in this &quot;Country have constantly the temperature of forty-eight degrees of 

 Fahrenheit s thermometer, is to be preferred to that of rivers,where it can be pro 

 cured in afufficient proportion, as the degree of cold in thefe is in the fame ratio 

 with that of the atmofphere till it declines to the freezing point,or that of thirty - 

 two. Though both when fpread out, forming a thin meet of ice on the furfaceof 

 the land, are beneficial in defending the roots of the grafs plants from too intcnfe 

 degrees of cold, and of thus preferving them in a inore healthy condition ; and it 

 is added, that thofc of fome forts of grafies arefuppofed to even vegetate beneath 

 the ice, as the rein-deer mofs in Siberia vegetates beneath the fnow, in a degree of 

 heat of about forty, which is the medium between that of the inferior furface of 

 thedifToIving fnow, or that of thirty-two, and that of the common heat of the in 

 ternal parts of the earth, which is forty-eight ; and in this manner the grafs pro. 

 duce in this cold country be confiderably increafed, fo as under proper manage 

 ment, to nearly double the ufual annual quantity under other circumftances.f 



In illuftration of thefe principles it may be obferved, that the water ifiuing 

 from fprings where they abound with the particles of gravel, or a flaty mouldering 

 kind of rock containing a large proportion of calcareous earth, are known from ex 

 perience to be better adapted to the purpofe than that which arifes from others 

 that do not contain fuch materials. Thedifferencc in the effecls, often fo vifibly 

 produced, has been accounted for, from watering one field from a fpring ifTuing out 

 of a chalky foil over thofe which take their rife in another, fimilar in every refpect 

 and management, except that the water applied arifes in, or flows through, a fwamp 

 or morafs,compofed chiefly of peat earth, or proceeds from filiations known to 

 contain none of. thefe fubftances. 



* Darwin s Phytologia, 4 Ibid. 



