ia ie 
On Gypsum. 
Read June 13th, 1809. 
Virginia, Port Royal February 10th, 1810, 
Dear Sir, 
Both Judge Peters and yourself have mistaken my 
experiment, respecting a field in corn, and another in 
bird-foot clover, owing no doubt to the obscurity of my 
language, These fields are not permanently occupied 
by either plant, but alternately by both. One field pro- 
duces a crop of corn, and the other being enclosed, re- 
ceives the benefit of a crop of ungrazed vegetable mat- 
ter. The succeeding year the ungrazed field is taxed 
with the crop of corn, and the corn field fed with the 
ungrazed vegetable. Both fields receiye annually a 
bushel of plaister to the acre ;_ in one it is sown upon the 
bird-foot clover in March or April, and in the other 
ploughed in at its fallow. The object is to ascertain 
whether an annual bushel of plaister to an acre, com- 
bined with a biennial relinquishment to the soil of its 
natural vegetable product, will enable it to be severely 
cropt every other year without impoverishment, or with 
an addition to its fertility. The first effect would suffice 
to check an evil, every where demonstrating the wretch- 
ed state of our agriculture; the second would be a 
cheap and expeditious mode of improving the soil, even 
where the state of agriculture is good. If doubts had not 
been again excited by the seasonableness of the last 
year as to rain, my convictions would have been settled 
