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the ornaments of life) would be endless, and the ex. 

 pence of procuring would exceed the value of the 

 acquisition : without these, neither metals, marbles, 

 salts, earths, nor stones, could be so easily or in such 

 plenty, provided, as is necessary for the use of man. 

 Earth is certainly the general food and stamen of all 

 bodies, yet we know of itself it can do nothing : it 

 must be connected by a cement, or it cannot form 

 stone; it must be softened and attenuated by mois- 

 ture and warmth, or it cannot enter into the alimen- 

 tary vessels of plants and animals. TJie parts of 

 earth which constitute the solids of any plants are ex- 

 cecding fi? e, and the common mass in which we plant 

 trees, is for the most part gravel, clay, aud sand, 

 which promote vegetation, but are too gross to enter 

 into, aud become the constituent parts of them. Water 

 must therefore be considered as the vehicle of more 

 solid nourishment, and the parent of the fluids : <he 

 earths, salts, and oils, are the great instruments of the 

 increase of solids. To trare fertility a little farther: 

 when the earth is softened and diluted heat rarefies 

 and evaporates the mixture ; the salts contained and 

 dissolved, are always active and promote motion ; the 

 elasticity of the air quickens and continues it : the 

 oils supple the passages, of which some are fitted to 

 secrete, arrest, and deposit the nutritious particle as 

 they pass ; some adapted (by the same secret hand, 

 vrhich conducts every part of the operation) to throw 

 off the redundant moisture by perspiration : the 

 earthly mixture composes the hard and solid parts, 

 and the genial, -little atmosphere of every plant gives 

 spirit, colour, odour, and taste. Herbs and fruits 

 being thus fed and matured, make the earU they 

 contain better prepared to pass info the still more cu- 

 rious and highly organized parts of animals. It is 

 x*asjr to see that this is rather a detail of the several 

 materials, and well-known instruments, conducing to 

 fertility, than the cause. Fertility is owing 1 to the 

 concert, fitness, arid agreement of all these, with some 

 volatile active principle, of which we kuow nothing 



