222 
On Lard Cheese. 
From all that has been stated, we can now draw the fol- 
lowing practical and economical conclusions : — 
1st. That the cultivation of roots and cereals deprives the 
soil of nitrogen, whilst that of grass and leguminous plants, 
temporary or permanent, on the contrary, causes it to accumu- 
late in the soil. That nitrogen being the most expensive 
manure to buy, it is not economical to devote part of the land 
absolutely to arable and part to grass, for whilst the one uses 
up the nitrogen, the other accumulates it in excess. On the 
contrary, it is preferable to alternate on the same piece of land 
the cultivation of roots and cereals with that of grass leys, 
so as, in a measure, to repair by the second the loss of nitrogen 
which the first cause to the soil. By this means cultivation can 
be kept up indefinitely, without purchased nitrogen, provided 
that the land be maintained in a fit state of richness as regards 
the mineral elements which are indispensable to healthy 
vegetation. 
2nd. The practical application of this principle is, that the 
temporary occupation of the land by a grass ley for two or three 
years, which takes its turn in the rotation of crops, should be 
preferred to permanent occupation by grass. We thus secure 
the improvement of the soil obtainable from the cultivation of 
clover, lucerne, vetches, «Scc. But as this class of plant will not 
succeed on every soil, temporary " leys " with graminaceous 
herbage ought to give, where leguminous plants do not succeed, 
analogous if not equally good results, and so assist us materially 
in solving the problem of producing cereal, root, and other crops, 
with increasing economy. 
VIII. On Lard Cheese. By X. A. Willaed, of Little Falls, 
Herkimer County, New York State. 
[lu a Letter to the Editor.] 
Dear Sir, — Knowing your interest in anything new as regards 
the dairy, I send you herewith my notes on an experimental 
creamery, which I visited on November 16, together with a 
drawing showing the construction and machinery of Wire's 
cheese vat. 
From the cut (p. 22G), and the accompanying description, I 
think you will be able to form a good idea of the apparatus. 
You have no doubt heard of a somewhat recent practice at 
some of our creameries for improving skimmed milk in cheese- 
