54 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Nitrate of sotla can be mixed with phosphatic and potash 

 fertilisers as required. 



Nitrate of Potash, the next item on the list, contributes both 

 nitrogen and potash. One ton weight yields 291 lbs. of nitrogen, 

 and 1,008 tons of potash. This will be found a useful manure 

 for supplying plants in a combined form with the necessary 

 quantity of readily assimilable potash, and of easily available 

 nitrogen. 



Experiments with Artificial Manures. 



I now direct your attention to some results obtained by 

 experiment, after the application of various artificial manures, and 

 of farmyard manure, to crops of potatos, tomatos, strawberries, 

 and peach trees. 



Table VI. illustrates the effect of various manures on the 

 growth of potatos at Rothamsted, Hertfordshire. The results 

 are a summary of produce obtained per acre over a period of 

 twelve years, 187G-1887, without manure, with farmyard manure, 

 and with various artificial manures, applied singly, and also in 

 combination. 



Table VI.— Experiments on Potatos at Rothamsted. Summary of 

 Produce of Tubers per Acre. Twelve years, 1876-1887. Quanti- 

 ties given in cwts. 



Manures per acre 



No manure .... 

 Superphosphate of lime, 3| cwts. 

 Mixed mineral manure 

 Ammonium salts alone, 400 lbs. 

 Nitrate of soda alone, 550 lbs. 

 Ammonium salts and minerals 

 Nitrate of soda and minerals . 

 Farmyard manure, 14 tons 



In the first place the data shows that the average produce of 

 potatos without manure is not quite two tons per acre. By 

 superphosphate alone the produce is raised to nearly 3} tons, a 

 gain of B4| cwts. per acre over the uninanured. By a mixed 

 mineral manure, containing besides superphosphate of lime, 



