On Gypsum. 157 



I have unremittingly continued the free and extensive 

 use of that substance ; and have not, in a single instance, 

 had occasion to repent, that I had used, or recommend- 

 ed it. It is on the contrary, among my most pleasing 

 recollections and reflections, that, more than any other 

 individual, I was instrumental in its general introduc- 

 tion here ; and in spreading throughout the country, a 

 knowledge of its existence, qualities, and benefits. The 

 success attending such efibrts, (amply repaid by tlie 

 gratification they afford) will be seen in all quarters, and 

 tlie general amelioration in husbandry, is a most esti- 

 mable reward. 



So far is the gypsum from injuring, by frequent repe- 

 tition, the soil to which it is applied ; that I am persuad- 

 ed it will perpetuate its fertility, if the husbandry be 

 good ; and common prudence, and attention to changes, 

 and cleanliness of crops by destruction of weeds, be 

 practised. On many parts of my fiu"ms the applications 

 of plaister have been at least, ten times repeated, in ro- 

 tations ; and other parts annually, in small quantities. 



If there be any difference in perceptible effect, I 

 think it favourable: the crops of clover are not so 

 over abundant; but more regular and certain, than 

 they were in my first essays. In the principles, on 

 which its operation can be most probably accounted 

 for, I am confirmed; by invai-iable experience. The 

 decayed, or putrefied substances on which the sul- 

 phuric acid operates, or by vvhich it is operated upon, 

 must be replaced ; when the use oi gypsum has exhaust- 

 ed, or neutralised them. This renovation may be pro- 

 duced, by turning in green manures, or animal sub- 

 stances : or strewing the plaister on a top dressing of 



