CONTENTS. 



92, Short account of Ingenhaiisz^ s 

 ideas, as to oil of vitriol being ser- 

 viceable to plants. Opinions of others. 

 92, 93, 94. Carbonic acid disengaged 

 by putrefaction^ ib. Ingejihausz' s 

 account of gypsum^ ib. Quantity of 

 plaister per acre: and mode of apply- 

 ing, 95, 96. Indian corn 96 — 7. Plais- 

 ter must be kept siiperficiaL Its ope- 

 ration not perceptible on zvinter 

 grain. 97, 8. Plaister with dung* — 

 Lot onxvhich it -was first strewed^ 

 98. Manures produce carbonic acid* 

 Plaister with animal or vegetable 

 manures^ most efficacious, 99, 100. 

 Mode and cause of operation^ and 

 repetition^ ib. Constant success with 

 plaister. Clover with plaister, agrees 

 the best of any other grass. Excessive 

 operation^ exhausts its powers in a 

 short time, 101. It is the sulphuric 

 acid^ which constitutes the operative 

 principle oi Y>l"disttr. postcript, 102, 

 3, 4. Dr. Priestly\ opinion of what 

 constitutes t\\e food of plaiits. Obser- 

 vations thereon, 105, 6, and opini- 

 ons of Ingenhausz and Chaptal^ ib. 

 English account of gypsum^ 108, 9, 

 10. Observations* thereon. 111, 12, 

 13, 14. Success of .Mr. Smythe^ in 

 England. Extract of a letter from 

 Robert Barclay Esq, of England. — 

 Proposition of experiment to banish 

 the Hessian fy ; by means of /?/flfZ5- 

 ter^ or oil of vitriol, 116, 117. Com- 



