140 SCIENTIFIC NEWS. 



ings or machines thus forwarded, will be reftored ; but the au- 

 thors may take copies, and may again receive their models or 

 machines, upon fubftituting regular drawings in place of them. 

 The Commiffioner of the Funds of the Inftitute will deliver 

 the gold medal to the bearer of the Secretary's receipt, if 

 given for the treatife, &c. ; but where no receipt exifts., the 

 author mufl himfelf appear, or fend his procuration. 



Subject of the Prize of Chemiftry, 



The clafs of mathematical and phyfical fciences having pro- 

 pofed in the year 8 the following prize queftion, to be decided 

 upon at the fitting above mentioned : 

 Prize queftion What are the characters ivhich dijiinguijli in vegetable and anii 



meats.'" 8 mal matters tJw f e Ptycfc fc rve <* s ferments, from thofe in which 



they caufe or excite fermentation. 



And none of the memoirs having fulfilled the conditions of 

 the program^ the clafs propofes the fame fubjecl again for the 

 year 12.' 



The prize will be a gold medal, of the value of one kilo- 

 gramme, which will be given at the fitting .of the \5 Germi- 

 nal of the year 12 (April 5, 1804). 



Prize Qucjlions from the Batavian Society at Haarlem. 



Prize queftioas* T ne Batavian Society at Haarlem has publiflied a number of 

 fubjecV of prizes at their fitting of May 1, 1802; among 

 which are the following : 

 Refpeaingma- 1. " How far it is known, from the lateft difcoveries in the 

 nures * phyfiology of plants, in what manner the different manures 



on different foils are favourable to the vegetation of plants ; 

 and what indications may we deduce from the knowledge re- 

 quired on this fubjec"r, to direct our choice as to manures, and 

 the fertilization of uncultivated and arid lands ?" 

 This queftion is continued to the lft of Nov. 1 80^!. 

 — motion of the 2. " What is the actual ftate of our knowledge refpecling 

 ■ ?• the motion of the fap in trees and plants ? In what manner 



can we acquire a more complete knowledge refpecling theob- 

 fcure and doubtful parts of the fubjed ? And is it poflible to 

 deduce, by decifive experiments, fuch indications as may be 

 ufeful for the cultivation of trees and plants ? M 



The Society has determined to repeat this queftion, to which 

 anfwers are to be fent before November 1, 1803. 



3. " The 





