Oration delivered before the Agricultural Society. 1 1 



of its produce by the creatures whom it fupports, a very incon- 

 fiderable quantity remains for manure. What then is to be 

 done? muft the land go on to be impoverifhed from year to 

 year? No. The animal, the vegetable and the mineral kingdom 

 muft be ranfacked for fomething to aid the growth of plants. 

 The aflies of wood and of peat, the muddy depofitions of 

 puddles and ponds, the unrefpirable portion of our atmofphere, 

 and fomc of the particles floating therein ; the various earthly 

 produ6lions of marie, chalk, gypfum, clay and lime, and likewife 

 the excrementitious matters of moft animals, are found by 

 experience, when properly employed, to promote direftly or 

 indire6lly the procefs of vegetation. When thefe things are 

 added to the foil, they a6l in one of thefe ways, i ft. They are 

 a pabulum plantarum, and materially contribute to the nutriment 

 of plants, or 2dly, They are ftimuli to plants, and by exciting 

 them to aCiion, caufe a greater abforption of food, a better 

 affmiilation of it, and confequently a more rapid and vigorous 

 growth; or 3dly, They fo alter and difpofe the earth in which 

 plants are rooted, that the radicles flioot more eafily and more 

 extenfively thro' it, or in other words, it becomes a better filter 

 for ftraining and applying nourifliment to their inhaling or 

 abforbing veftels. Here, however, it is necelfary for me to 

 paufe ; for in order to decide in which of thefe ways manure 

 operates, it v^ould be neceflary to take into confideration a 

 much greater alfemblage of fafts than the limits of this attempt 

 permit; and as the folution of thefe queftions involves the 

 intricate xiifcuITion of what the food of plants is, whether water. 



