560 Report of Experiments with different Manures 



traced by confining attention to the column showing the average 

 annual produce over the 3 years^ and to the concluding one of the 

 Table (I.) showing the average anmial increase by manure. These 

 records relate, as will be remembered, to the produce of one 

 cutting only. An estimate will be given further on, as to the 

 actual and relative amounts of hay, to which the after-feed on the 

 several plots was probably equivalent. At present it is only 

 necessary to consider how far the consumption of the after-grass 

 upon the land should influence the judgment to be formed of 

 the effects of the different manures according to the weights of 

 the produce of the first crop alone. On this point it may be 

 remarked, that the knowledge we possess as to the average pro- 

 portion of the nitrogen and of the mineral matter of the food 

 consumed by stock, which they probably finally store up in their 

 bodies (and in the case of nitrogen exhale), is such as to lead to 

 the conclusion that the land would lose comparatively little of 

 these manuring substances by the consumption upon it of the 

 after-grass by sheep. By far the larger proportion of these con- 

 tained in the second crop of one year would, therefore, remain 

 towards the produce of the first crop in the succeeding year. 

 Taken over a series of years, the annual produce yielded in 

 the first crop will thus pretty closely represent the average annual 

 result of the manure on any particular plot ; at any rate suffi- 

 ciently so for a general comparison of the effects of one manure 

 with that of another. 



On one of the unmanured plots the average annual produce of 

 hay was 1 ton 3 cwts. 1 qr. 10 lbs. ; and it varied but little from 

 year to year. The duplicate unmanured plot was- somewhat 

 shaded from the afternoon sun. It gave in the first two years 

 about 2 cwts. less of hay annually per acre than the other, but in 

 the third year as much as 8 cwts. of hay more. The fact was, as 

 the result of the after-feeding showed, that this second plot, 

 though it gave less mown hay in the first two years than the 

 first plot, gave, on the other hand, more aftergrass in those 

 years. Hence there was less removal from the land in the first 

 two years ; and, compared with the other plot, some accumulation 

 of manuring matter for the first crop of the third season. The 

 average annual yield of mown hay on the duplicate plot was, 

 however, only If cwts. more than on the other. The mean of 

 the two may therefore be fairly taken as the average annual yield 

 of the land and seasons in question. This amounted to 1 ton 

 4 cwts. and 3 lbs. of hay, as the standard unmanured produce of 

 the experimental meadow-land. 



Saicdast contains very little of either nitrogen or mineral 

 matter ; but, upcm high authority, it has been stated to produce 

 great effects as manure, by virtue of the solvent action of the car- 



