C 206 ] 



Read July 10th, 1810. 

 Sir] 



The following contains a confirmation of the opinion 

 I have always held, as to the operative principle of the 

 plaister of Paris. It will be seen in my '* agricultural 

 inquiries on plaister of Paris,'''' published in 1797, that 

 I therein mentioned, as a conjecture, what reiterated 

 experiment has since proved. I translate from the 

 French^ a sketch of the memoir e on the subject, sent 

 to me by a friend. It contains information worthy of 

 being promulgated ; though much of it is here, more 

 confirmatory than new, as to the plaister. But I do not 

 recollect that any experiments have been made with 

 SULPHUR, for the purposes stated in the memoire, 



Richard Peters. 

 20th June, 1810. 



Dr. James Mease. 



Secretary of the Agric* Soc. Fhilad. 



The efficacy of sulphur on vegetation. 



" ^ ]\i e M 01 r E of M. B E R A R D t/ic elder a trader at 

 p o N T - L I E u L E s L E MANS, and member of the society 

 of that town^ treating on the use of plaister or gyp- 

 sum, employed as a manure; containing observations 

 curious and useful in agriculture ^ 



"il/. j^d-mr^ observed, with admiration, in many jour- 

 nies on the borders of the lake of Geneva, in Savoy^ 



