62 AdCOUNt OF BOOKS, 



Thefe philofophers followed Mr. Chenevlx*s procefs with 

 great care, but did not produce that metallic body. In th« 

 precipitation of nuiriate of mercury and muriate of platina^ 

 they had a black powder, which always afforded the metals 

 feparate from each other. 



Richter was not more fuccefsful. He verified that the green 

 fulphate of iron does not 'decompofe either the muriate of 

 mercury or that of plat Jna. The other fa(5>8 he obferved were 

 to the fame, effect as thofe of Rofe and Gehlen. He always 

 found the mercury of his precipitate feparated from the platina 

 by heat* 



Trait(i ciementaire d'Hidoire Naturelle, &:c. /1?t elementary 

 Treatife on Natural Hijionj, tyA.M. Constat Dume'ril;' 

 Compoftd by Order of Government for the Ufe of the National 

 Lyceums, 1 Vol. 8vo. Paris*, 



llementary There Is not one of the fciences, the elementary works of 



rarh)ftorv"veiT ^^^'^^ havd been fo long neglected as natural hiflory. Some- 

 ^feftivc. times this title has been given to coliedions of tales fit only to 



amufe children, but not calculated to make them acquainted 

 with nature as a whole, and with the progrefs of the fcience ; 

 at other times authors have entered into difcuffions tooabftrufe, 

 or contented themfelves with a mere nomenclature, always 

 dry and fteriie to beginners, to whom names give no idea of 

 Mr. D. has pur- objedls with which they are unacquainted. Mr. D. has pre- 

 rfiDd^"^"^ ferved a jufi; medium between thefe extremes, while he ob- 

 ferves an accurate and methodical arrangement. He makes 

 us acquainted with the whole of the produ6iions of nature, and 

 the method of ftudying and clafling them, choofing for ex- 

 amples in every fe6lion fuch as are moft remarkable for their 

 ufes or Angularity; he continually excites the attention and 

 curiofity of his pupils ; and he prefents to them a number of 

 fads necefiary to be known. 

 His arrangement In this work Mr. D. has adopted an arrangement, the reverfe 

 Krmoftfim'^le ^'^' "^'^^^ ^^ ufually employed in books of natural hiflory ; that 

 things to the is, he always proceeds from the mofl fimple to the moft corn- 

 more complex, pjgjj He begins with unorganized fubftances, proceeds hence 

 to plants, and laflly to animals ; and in thefe he commences 



* Bulletin des Sciences, No. 90, p. 23G, Sept. 1804. 



with 



