326 NATURAL HISTORY 



LETTER XLI. 



TO THE SAME. 

 DEAR SIR, SELBORNE, July 3, 1778. 



IN a district so diversified with such a variety of hill 

 and dale, aspects and soils, it is no wonder that great 

 choice of plants should be found. Chalks, clays, sands, 

 sheep-walks and downs, bogs, heaths, woodlands, and 



experiments, instituted at Woburn Abbey and conducted under the super- 

 intendence of the late George Sinclair, have furnished data for judging 

 how most probably two blades of grass may be made to grow where one 

 only was before found. The object of the experiments was to ascertain 

 what kinds of grass yielded the largest crops and the greatest quantity 

 of nutriment; and to determine the soils which were best adapted to each 

 of them. Their consequence was the publication, in 1816, of the Hortus 

 Gramineus Woburnensis, or an Account of the Results of the Experi- 

 ments on the Produce and nutritive Qualities of different Grasses and 

 other Plants, used as the Food of the more valuable domestic Animals. 

 " Spots of ground, each containing four square feet, were enclosed by 

 boards in such a manner that there was no lateral communication between 

 the earth enclosed by the boards and that of the garden : the soil was 

 removed in these enclosures, and new soils supplied, or mixtures of soils 

 were made in them, to furnish, as far as possible, to the different grasses 

 those soils which seem most favourable to their growth, a few varieties 

 being adopted for the purpose of ascertaining the effects of different soils 

 on the same plant." Most of the species were grown on sandy, clayey, 

 loamy, and peaty soils, of various proportions, the chemical composition 

 of each being ascertained by Sir Humphry Davy ; and the quantity of 

 nutritive matter afforded by the crop was also determined by a simple 

 process indicated by the same eminent chemist. " The grass, in its green 

 or dry state, was submitted to the action of hot water till all its soluble 

 parts were taken up: the liquor was then separated from the woody fibre 

 of the grass by means of blotting paper : it was then evaporated to dry- 

 ness. The product, or solid matter, is the nutritive matter of the grass," 

 consisting, " for the most part, of five distinct vegetable substances, viz. 

 mucilaginous, saccharine, albuminous, bitter extractive, and saline 

 matters." 



Under this treatment, as an instance, it may be mentioned that it was 

 found that the cock's foot grass, when cultivated on a peat soil, produced 

 one-sixth more in weight than on a sandy loam ; but that the grass was 

 of an inferior quality as to nutriment; so that the crop, although heavier, 

 was of less value in the proportion of nine to eight : that the first leaves 



