17 



received annually for eight years, 1856-63, 14 tons of farm- 

 yard manure, and has since been left unmanured. Calcula- 

 ting precisely as before the practical value of the residue of 

 this manure, it appears that for nine years it yielded a pro- 

 duce greater than that given by the land before farmyard 

 manure was applied ; and that during these nine years it 

 produced a total excess of crop amounting to 6 tons of hay 

 per acre. Valuing hay at 70s. a ton, we obtain 21 as the 

 gross return per acre from the residue of the farmyard 

 manure. From this gross sum serious deductions have to 

 be made on the lines already mentioned, if we would arrive 

 at the sum fairly due to an outgoing tenant as compensation 

 for the unexhausted value of his manure. 



The far greater compensation due in the case of the grass 

 land, notwithstanding the much smaller manure residue in- 

 volved, teaches us an important lesson. It will always be the 

 case that slowly acting manures, if really suitable to the soil, 

 will yield a larger return on grass than on arable land. On 

 permanent grass land any waste of plant food in the soil is 

 reduced to a minimum. 



At Woburn, in the experiments conducted by the Eoyal 

 Agricultural Society on the continuous growth of wheat and 

 barley, there are plots on which well-rotted farmyard manure 

 has been applied as a top-dressing during twenty years, 1877- 

 96. After the first five years the plots were in each case 

 divided, one-half being subsequently unmanured, while on the 

 other half the farmyard manure was continuously applied. 

 We have thus, both in the barley and wheat field, plots which 

 received farmyard manure for five years, and have for fifteen 

 years been cropped without manure. Such an experiment 

 should supply us with facts very pertinent to the question 

 before us ; the results obtained are, however, somewhat diffi- 

 cult to interpret. 



The manure used in these experiments was prepared by 

 feeding fattening bullocks in deep stalls having concrete sides 

 and bottom. These bullocks received decorticated cotton- 

 cake, maize meal, turnips, and straw chaff. The whole of the 

 food and litter employed was weighed, and its composition 

 ascertained by chemical analysis ; it was thus known how 



