332 Chemical Changes in the Fermentation of Dung. 
entertain to thorn. But one may be here mentioned in the hope 
that others will repeat it, because it is more convincing than a 
thousand arguments. 
A quantity of the heap Experiment V. was digested with water 
and gave a light brownish solution neutral to test-paper. This 
was carefully filtered twice and then mixed with caustic potash 
to test the presence of ammonia. None was given off, but a 
brown flocculent substance collected upon the surface of a per- 
fectly clear white fluid. This was filtered and the brown sub- 
stance burnt when it evolved ammonia copiously. It also gave 
off ammonia slowly when exposed to the air. 
Here then was nitrogenized matter in the form of as true a salt 
as the muriate of ammonia which the farmer buys of the manu- 
facturing chemist for manure. Moreover it was so combined 
that even potash could not expel it. It Avas perfectly soluble in 
water and therefore ready for plants to take up as food. In 
manure thus fermented I have little doubt will be found an 
adequate remedy for weak straio upon well farmed land ; and 
that the economy of nitrogen will lead to an increase of grain 
can hardly admit of doubt. In short here was what NATURE 
makes when she decomposes substances in the earth, a perfect 
manure according to the highest authority.* 
* Value of Manure of Heap V. 
Experiment I. — Part of this heap was employed for potatoes. Forty pounds 
weight of " Haigh's seedling" (kidney) potatoes were planted with it April 4th, 
1855, 3 feet 3 inches fiom row to row, and 18 inches from set to set, upon land of 
fair quality and in good condition. 
Under date August 17, 1855, I have this memorandum relative to the crop: — 
Average yield 31 fold. Sets 5^ packs (of 240 lbs.) each per acre ; 31 X 5-J = 170 
packs per acre. Present price lUs. per pack ; produce = 85/. per acre. This ex- 
periment is not offered for more than it is worth. Part of this large produce is 
undoubtedly due to peculiarity of management which this is not the place to 
describe. It may also fairly be doubted how far a crop off five rods of ground will 
justify reasoning applied to a field or a farm. No account was kept of the quantity 
of manure applied, though I do not think it was much, if anything, above an average. 
But even after every allowance I think the most sceptical will admit that the 
manure employed must have been better than common. Savoys were planted 
between the rows of potatoes in the last week of June and they are now, Octo- 
ber 20th, an excellent crop. 
Experiiucut II. — The following appears beyond objection : — An acre of light land, 
of medium (juality and in fair condition, was ploughed and planted with York regent 
potatoes, half on the 3rd and half on the 1 1th of May. The sets were of the ordi- 
nary kind purchased as wanted. Drills were made by the plough 2 feet 2 inches 
apart, and the sets planted about 15 inches from each other in the row. Tlie rows 
ran east and west. Twelve one-horse cartloads of manure were given to the acre, 
besides three cartloads [of ashes obtained by burning vegetable rubbish. The po- 
tatoes were once handhoed and then earthed by the plough July 7th. Tliey were 
much admired by neighbouring farmers during growth and on the 31st of August 
were sold upon the land for 20/. 5s. per acre, to be cleared by September 28th. I 
regret my inability to learn the exact produce. Several experieuced dealers who 
saw the crop as it was thrown up estimated it at from 72 to 80 packs per acre. 
This experiment as the complement of the former seems every way satisfactory as 
to the q'uiliti/ of manure treated as recommended. 
