On Agricultural Chemistry. 



231 



these remarks do not apply to those places in which the climate 

 varies much from that of London; but I have given what I believe 

 to be the general character of the crops within a circle of 100 

 miles from London. 



The soil upon which my experiments were tried consists of 

 rather a heavy loam resting upon chalk, capable of producing 

 good wheat when well manured, not sufficiently heavy for beans^ 

 but too heavy for good turnips or barley. The average produce 

 of wheat in the neighbourhood is said to be less than 22 bushels 

 per acre, wheat being grown once in five years. The rent varies 

 from 20s. to 265. per acre, tithe free. The fields selected for 

 purposes of experiment had been reduced to the lowest state of 

 fertility by removing a certain number of corn crops without ap- 

 plying any manure, and wheat and turnips were chosen for the 

 subjects of investigation. The wheat -field consists of 14 acres, 

 the crops removed since it was manured barley, peas, wheat, oats. 

 In 1844, the first experimental wheat-crop was harvested, and the 

 fourth is now growing. The turnip-field had not long been 

 taken in hand, and was known to be in so poor a condition that it 

 was at once put under experiment, and in 1843 the first crop of 

 turnips was sown and they have been continued each year since, 

 the produce being removed and weighed. The wheat-field was 

 divided into a certain number of equal spaces, of which one has 

 been left unmanured and one received 14 tons of dung every 

 year ; the remainder of the plots received different descriptions 

 and quantities of artificial manures. 



The following table gives the climate of the three years from 

 the beginning of May till the end of October. I have considered 

 the climate as affecting the grass to be that of April and May ; 

 wheat-climate to commence with May and end with August; 

 turnip season to begin with June and end with October : — 



It will be seen that the two spring months of 1844, April and 

 May, were unusually dry ; the quantity of rain and the number 

 of days in which it fell were both small ; the summer was hot 

 and dry, and the autumn moderately rainy. An entire absence 

 of the climate necessary for an enhanced accumulative and cir- 

 culating condition of plants prevented the favourable growth of 

 the spring crops, and a hot and dry summer favoured the depo- 

 siting and elaborative condition, and produced good quality of 

 grain. In 1845 the great number of wet days and the low tem- 

 perature of the summer were highly favourable to a circulatory 

 condition of the plant, consequently green crops of every de- 

 scription and straw were unusually abundant, and grain of bad 

 quality. In 1846 the spring was very favourable to a circulating 

 condition, producing luxuriant crops of grass and clover. The 

 month of June, when the grain was forming seed, had a tempera- 



