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XVII. On different Sorts of Lime used in Agriculture . By 
Smithson Tennant, Esq. F. R. S. 
Read June 6, 1 799. 
I was informed last summer, that in the neighbourhood of Don- 
caster, two kinds of lime were employed in agriculture, which 
were supposed to differ materially in their effects. One of these, 
which was procured near the town, it was necessary to use 
sparingly, and to spread very evenly over the land ; for it was 
said that a large proportion of it, instead of increasing, diminished 
the fertility of the soil; and, that wherever a heap of it was left in 
one spot, all vegetation was prevented for many years. Fifty or 
sixty bushels upon an acre, were considered to be as much as 
could be used with advantage. The other sort of lime, which 
was obtained from a village near Ferry-bridge, though consi- 
derably dearer, from the distant carriage, was more frequently 
employed, on account of its superior utility. A large quantity 
was never found to be injurious ; and the spots which were en- 
tirely covered with it, instead of being rendered barren, became 
remarkably fertile. The different properties ascribed to these 
two kinds of lime were so very distinct, that it seemed pro- 
bable they could not be imaginary ; and it therefore appeared 
to be worth the trouble of ascertaining them more fully, and 
of attempting to discover the nature of the ingredients from 
