On Permanent and Temporary Meadows and Pastures. 207 
atmosphere. Such, in my opinion, is the explanation, which 
results from all that we know about vegetation ; and it removes 
the contradictions which have so barred the minds of those 
who are unwilling to admit the intervention of atmospheric 
nitrogen in the nourishment of plants. By this explanation, 
which is simple and yet well founded, all becomes clear, and 
the problem of the economical production of crops in general, 
and of hay in particular, is solved. 
Practically, it will be sufficient to give to the soil, under 
favourable conditions, in the form of an assimilable manure, 
the small amount of nitrogen necessary for the plant to make its 
first growth ; and the crop will give back to the earth and to 
the farmer more than ten times the amount of nitrogen so 
supplied to it. 
On strong soils which quickly fix nitrogenous salts, and hold 
them with energy, I advise a dose of 267 lbs. to the acre as a 
top-dressing after the last ploughing. On light soils where the 
salts sink quickly, I think it would be imprudent to exceed 
89 lbs. to the acre, for it would only be to expose oneself to loss. 
But it will be useful to give a second dose of 89 lbs. about the 
middle of the season. Experience will teach every one the 
limit, at which he must stop if the conditions of growth from 
time to time are carefully noted. 
Even where farmyard-manure has been ploughed-in in large 
quantities, before laying down to grass, it will nevertheless be 
useful to add nitrogenous salts as a top-dressing after the last 
ploughing, for the purpose of promoting the early development 
of the plant as above explained. 
Finally. — Laying-down to grass requires, that, whilst taking 
account of the chemical composition of the soil as shown by 
analysis, there should be — 
1st. A provision of fossil-phosphates and lime as a bottom- 
dressing of manure, if the soil is not sufficiently rich in lime 
and phosphoric acid. This expense should be spread over the 
duration of the ley ; 
2nd. From 21'168 to 26'48 cubic yards of farmyard-manure per 
acre, to furnish the phosphoric acid, potash, and nitrogen 
necessary for the first crops, an outlay to be spread over the 
first 3 or 4 years : or if no farmyard-manure is obtainable, it 
must be replaced by a dressing of chemical manure applied after 
the last ploughing and containing per acre 
Assimilable phosphoric acid 44-60 lbs. 
Potash 133-80 lbs. 
Nitric Nitrogen from 13-38 to 40-14 lbs. 
The cost of this varies from about 53*. 5c?. to 81s. Zd. per 
