22 FARMYARD MANURE. 



manure appeared to have gone either into the air or to have been 

 washed into the soil. It was necessary therefore to scrape the 

 soil as close as possible in order not to lose any of the manure ; 

 and it is due to this circumstance that at the conclusion of the 

 experiment a very much larger proportion of insoluble mineral 

 substances was found than in the perfectly fresh manure. I may 

 mention, however, that the whole mass of the spread manure has 

 been most carefully mixed before a sample was taken for ana- 

 lysis. The earthy matters I have every reason to believe were 

 intimately mixed with the manure ; and since the composition of 

 the entire mass has been calculated from the data already fur- 

 nished, the general deductions which may be derived from my 

 experiments are not affected by this circumstance. In speaking 

 of the loss which this manure sustained in keeping, I will select 

 the more important fertilising constituents for illustration, 

 and in reference to them beg to make the following observa- 

 tions : 



1. The weight of the whole manure, when spread out in an 

 enclosed yard, amounted to 1652 Ibs. In this quantity were 

 present 40*97, or nearly 41 Ibs. of soluble organic matters. 

 After the lapse of six months only 16J Ibs. were left in the 

 manure ; in nine months barely 5 Ibs., and after twelve months 

 merely 4 Ibs. 



Thus only about l-10th part of the original quantity of soluble 

 organic matters was left over by keeping fresh farmyard manure 

 spread out in an open yard. 



2. The nitrogen contained in the 41 Ibs. of soluble organic 

 matters amounted to 3'28 Ibs. After six months only 1-19 Ibs. 

 of nitrogen, in the state of soluble compounds, was left ; after 

 nine months little more than ^ lb., and after twelve months 

 only -^ of a lb. In other words, the nitrogen in the state of 

 soluble compounds has disappeared almost entirely in the course 

 of a year. 



3. In an equally considerable degree the soluble mineral 

 matters were dissipated in the manure. Originally the manure 

 contained 25'43 Ibs. of soluble mineral matters. After six 

 months this quantity became reduced to 14'41 Ibs ; after nine 

 months to 6*47 Ibs., and after a lapse of twelve months to 

 5-52 Ibs. 



On the whole the manure thus lost 78*2 per cent, of the ori- 

 ginal quantity of soluble mineral matters. 



4. Still more striking is the loss in insoluble organic matters. 

 In the fresh manure were present 425 67 Ibs. of insoluble organic 

 substances. In the course of six months these became reduced to 

 163*79 Ibs. ; a further exposure of rather more than three months 

 to the weather reduced this quantity to 106*81 Ibs., and after 

 twelve months merely 94*45 Ibs. were left over. The manure 



