39 



lished by Mr. Gay-Lussac in the memoirs of 

 the society of Arcueil* ; 



A phosphoric eudiometer by Reboul. By the 

 nice researches of Mr. Thenard, on charcoal 

 mixed with phosphorus, it is proved, that the 

 slow action of this acidifiable basis-}- yields 

 results less exact than strong combustion ; 



An apparatus hy Paul, proper to determine with 

 the greatest precision the degree at which wa- 

 ter boils at different heights, above the level of 

 the ocean. The thermometer with a double 

 nonius had been constructed from the appa- 

 ratus, which Mr. de Saussure employed in his 

 excursions ; 



A thermometrical lead by Dumotier, consisting 

 of a cylindric vase, furnished with two conical 

 valves, and enclosing a thermometer ; 



Two areometers of Nicholson and Dollond ; 



A compound microscope of Hofmann, described 

 in the history of the Cryptogamise by Mr. Hed- 

 wig ; a standard metre by Le Noir ; a land sur- 

 veyors chain ; an assay balance; a rain gauge ; 

 tubes of absorption to indicate small quanti- 

 ties of carbonic acid and oxygen, by means of 

 lime-water, or a solution of sulphuret of pot- 

 ash; some Hauys electroscopical apparatuses ; 



* Vol. 2, p. 235. See also the memoirs in the composition 

 of the air which I published conjointly with Mr. Gay-Lussac 

 in the Journal de Physique, vol. lix, p. 129, and my Zoolo- 

 gical Observations, vol. i, p. 256. 



f Bulletin of the Philomathic Society, 1812, No. 37, p. 93. 



