PL A 



PL A 



329 



mix them with composts, in such 

 proportions as may be most hkely 

 to ascertain their lertihzing quali- 

 ties, if any such exist. 



It has been affirmed that gypsum 

 is not useful as a manure in the 

 vicinity of the sea. And (he wri- 

 ter last above quoted observes, 

 that "on the hypothesis that sea- 

 air destroys the fertilizing princi- 

 ple in gypsum, Mr. R. Bakcwell, 

 a correspondent of the Montlily 

 IMagazine, proceeds to account for 

 its failure as a manure in so many 

 parts of the country. It is enough 

 to dispel this opinion, to name the 

 county of Kent, in England, as the 

 place where it has most fully suc- 

 ceeded." It has likewise been used 

 on Long Island, in America, in the 

 vicinity of the sea, with good eliect, 

 and in the state of Maine on the 

 margin of the sea. 



Dr. Jos. E. Muse, of Maryland, 

 in an essay on the subject of gyp- 

 sum, and its mode of operation, 

 published in the American Farmer, 

 vol. I. p. 338, gives it as his opi- 

 nion " That the chief, if not the 

 whole cause of the efficacy of gyp- 

 sum in promoting vegetation, is to 

 be found in its tendency to become 

 phosphoric. This gentleman pro- 

 duces many chemical facts, and 

 deductions therefrom, to shew that 

 gypsum by exposure to the atmos- 

 phercy becomes phosphoric ; and 

 that phosphorus exists in vegeta- 

 bles. 



Dr. Gorham, in a paper read 

 before a Society in Boston, July 

 ]6th, 1813. and published in the 

 Massachusetts Agricultural Jour- 

 nal, vol. III. No. 2., gives it as his 

 opinion, that " when the plaster of 

 42 



Paris is applied to the seed, it stimu- 

 lates the little rod, the action of the 

 vessels is thus increased, absorp- 

 tion goes on more rapidly, and it 

 acquires more nourishment in a 

 given time than in oidinary circum- 

 stances ; the consequences are a 

 quick growth and enlargement of 

 the organs," <s:c. 



Col. Taylor, of Virginia, ob- 

 serves, in substance, that he sows 

 of plaster from three pecks to one 

 bushel to the acre. Sown on 

 clover in the spring, it benefits it 

 considerably. And in any other 

 mode he ploughs it in. The best 

 way of using it is in the spring upon 

 the long manure of the preceding 

 winter, to be ploughed in with it. 

 He thinks it a valuable ally, but 

 by no means a substitute for ma- 

 nure. That there should be in- 

 tervals of two, three, or four years 

 between applying it to the same 

 land. That its effect is graduated 

 by the quantity of vegetable mat- 

 ter on which it is sown. That 

 upon close grazed land it does lit- 

 tle good at first, and repeated ^ 

 v.'ould become pernicious ; and 

 that it must be united either with 

 long manure of the winter, or the 

 ungrazed vegetable cover produc- 

 ed in the summer. 'I'hat all crops 

 are ultimately improved by its im- 

 proving the soil, even when its 

 effects are tiot immediately visible, 

 but he does not recommend it as 

 a top-dressing, except for clover. 



M. Canolie, a French writer, 

 observes, th;U plaster acting, or 

 operating chiefly on the absorbent 

 system of plants, its cflectsare not 

 like those of manures buried in the 

 soil, which act principally on tl)e 

 roots. The latter according' to 



