DR. DAUBENY ON THE ROTATION OF CROPS, ETC. 249 



rials, and for a renewed extrication of its useful ingredients, to take place ; 3rdly, to 

 produce by the various methods in daily use, such a stirring and pulverization of 

 the ground, as may admit of a more thorough admission of air and moisture, and 

 consequently accelerate the process of disintegration in a greater degree than would 

 take place under natural circumstances. 



Examples will occur to every one of the successful adoption of each of these three 

 practices : of the first, in the ordinary process of manuring, and especially in the be- 

 neficial consequences resulting from the use of bones in the exhausted pastures of 

 Cheshire and other similar localities ; of the second, in the system so general in the 

 early stages of agriculture, of allowing land to remain at rest for a certain period 

 with a view of restoring to it its exhausted powers, — a method which would be ab- 

 surd, if the alkalies, phosphates, and other of the more scanty ingredients were ab- 

 solutely deficient, but which would be likely to prove efficient, if they were only 

 locked up within the recesses of the soil, and required time to render them active; 

 of the third, in the practice resorted to by Jethro Tull, who boasted that he could 

 realize an abundant crop year after year without manure, provided the ground were 

 only stirred and broken up sufficiently, — a statement which seems confirmed, by some 

 of the results of spade husbandry, and in a certain degree by those detailed in this 

 paper, with respect to the permanent crops which are herein mentioned as having 

 been made the subject of experiment. 



The choice between the above three methods will of course be determined in each 

 instance by a balance of economy, and although in general this latter consideration 

 will incline the farmer to prefer the ordinary method of manuring, either to the 

 sacrifice of a year's produce, as in the second method, or to the expenditure of labour 

 required to put into practice the third, still there may be cases where it might better 

 answer his purpose to resort to one or other of them, either as being more advan- 

 tageous in itself, or more suitable to the circumstances of the case. 



At any rate it may be important for him to be assured, that at the very time he is 

 ransacking the most distant quarters of the globe for certain of the mineral ingre- 

 dients required for his crops, he has lying beneath his feet in many instances an 

 almost inexhaustible supply of the very same. 



For there seems no reason to doubt, that the whole mass of rock, which constitutes 

 the subsoil in the secondary and tertiary districts of this country, is as rich in phos- 

 phates and in alkalies, as the vegetable mould derived from its decomposition ; and 

 although the soil, in which the experiments in my garden were conducted, possessed 

 a depth nearly three times as great as the average of those in which farm produce is 

 generally raised, yet on the other hand, the amount of phosphates and of alkaline 

 ingredients reported to be present in them, appears in many instances greater than 

 that determined in the case before us. 



Thus Dr. Ure* gives an analysis of a soil in the parish of Hornchurch, Essex, 



* Journal of the Royal Agricultural Society. 



