That salt in large quantities rendered land barren, 
was known long before any records of agricultural 
science existed. We read in the Scriptures, that 
Abimelech took the city of Shechem, “ and beat 
down the city, and sowed it with salt that the 
soil might be for ever unfruitful. Virgil reprobates 
a salt soil ; and Pliny, though he recommends 
giving salt to cattle, yet affirms, that when strewed 
over land it renders it barren. But these are not 
arguments against a proper application of it. Refuse 
salt in Cornwall, which, however, likewise contains 
some of the oil and exuviae of fish, has long been 
known as an admirable manure. And the Cheshire 
farmers contend for the benefit of the peculiar pro- 
duce of their country. 
It is not unlikely that the same causes influence 
the effects of salt, as those which act in modifying 
the operation of gypsum. Most lands in this 
island, particularly those near the sea, probably 
contain a sufficient quantity of salt for all the pur- 
poses of vegetation ; and in such cases the supply 
of it to the soil will not only be useless, but may be 
injurious. In great storms the spray of the sea 
has been carried more than 50 miles from the 
shore ; so that from this source salt must be often 
supplied to the soil. I have found salt in all the 
sandstone rocks that I have examined, and it must 
exist in the soil derived from these rocks. It is a 
constituent likewise of almost every kind of animal 
and vegetable manure. 
Besides these compounds of the alkaline earths 
and alkalies, many others have been recommended 
for the purposes of increasing vegetation ; such 
