208 Royal Society of the Sclemfes at Prague, &c. 



The papers must be transmitted to the secretary's office 

 of the Institute, free of postage, or to the perpetual secretary 

 of the Class of the Mathematical and Physical Sciences. 



None of the papers will be returned, but the authors may 

 take copies of them if they think proper. 



A vacancy having occurred, by the death of Dr. Priestley, 

 *mong the foreign associates of the National Institute, 

 M. Klaproth, chemist of Berlin, who is known as the dis- 

 coverer of three new metals and four earths, was elected to 

 that place. The other candidates proposed were: M. Pi- 

 azzi, astronomer, of Palermo; Jacquin, botanist, of Vienna; 

 Scarpa, anatomist, of Pavia ; Vahl, botanist, of Copenhar 

 gen ; Mascagni, anatomist, of Sienna ; Mr. Watt, of Bir~ 

 roingham ; Verner, mineralogist, of Freyberg ; Mr. Dal- 

 rymple, the geographer ; and the celebrated traveller Hum- 

 boldt. 



THE ROYAL SOCIETY OF THE SCIENCES AT PRAGUE 



Has proposed the two following prize questions : 



" I. To discover the means, besides those of the police, 

 for putting an end to, or at least lessening, the various 

 kinds of adulteration practised in regard to provisions.'* 



It is well known that there are three principal causes of 

 adulteration : the mixture of corrupted matters ; the intro- 

 duction of foreign and prejudicial matters ; the preparing 

 and keeping food in dangerous or unhealthful vessels. The 

 society is therefore of opinion that it will be doing a great 

 service to mankind to collect all the means already known 

 and published by chemists for remedying these inconve- 

 niences, provided they be accompanied with simpler, less 

 expensive, and more certain processes ; and that they be 

 described in such a manner as to render them practicable 

 and intelligible to peasants. The competitors, however, 

 will still be at liberty to propose means of their qwn inven- 

 tion. The memoirs must be written in German.. The 

 prize will be 500 florins, and 400 copies of the successful 

 memoir, which will be printed at the expense of the society. 



"II. To examine and appreciate all the sources from 

 which materials may be drawn to throw light on the his- 

 tory of Bohemia, and to point out and give a character of 

 rhe principal historical works which treat of that country." 

 The prize will be 300 florins, and 400 copies of the success- 

 ful memoir, printed as the preceding. The memoirs must 

 be written in German, and transmitted, free of postage, to 

 ihv secretary of the society before the 1st of January 1806. 



XXXVIL ih 



