SCIENTIFIC NEWS. 143 



The prefent article is taken from Millin's Magafui Encyclope* 

 diqite, who does not fay whether the wooden cylinders were 

 moved In rotation or otherwife, nor how they were applied 

 and preffed againft the firings. The leading fact of this notice 

 feems to be, that there are certain kinds of wood, and perhaps 

 certain refinous or other matters to be applied to them, that 

 will produce the effect of a bow upon wire firings in a fuperior 

 manner. It is indeed probable, that we do not yet pofTefs 

 much knowledge of the art of producing tones by the powerful 

 expedient of bowing, or light friction; and mechanics have 

 (till an ample field for applying this method with force, pre- 

 cision, and rapidity to the more compounded inftruments. 



Saverien. 



On the 23th of May laft died Alexander Saverien engineer Death of 

 of the French marine; who has been ftxty years known to the avenen * 

 fcientific world, for his writings on navigation and the theory 

 of building, rigging and maneuvering fhips. He has written 

 accounts of the infiruments for making obfervalions at fea ; 

 a marine dictionary ; a dictionary of the mathematics ; a dic- 

 tionary of architecture; an hiftory of modern philofophers, 

 and an hiftory of the progrefs of the human underflanding. 

 His works indicate a confiderable fliare of talent and very ex- 

 teniive knowledge. For many of the laft years of his life he 

 was poor and infirm, and was much indebted to the cares of a 

 fervant who continued with him from motives of attachment. 

 He died at the age of eighty-five, leaving behind him a widow 

 Iikewife very aged and in want. 



Pure and beautiful Centfe. 



Mr. Van Mons informs us, that, if lead afhes be diftblved ?\\xz and beau- 

 ft -i fufficient quantity of dilute nitnc acid by the help of a tUui cerufc " 

 gentle heat, filtered, and precipitated by chalk in impalpable 

 pow ler^ the precipitate, when v. afhed and dried, will be the 

 [Vurei: and mofi be iititul cerufe pofiibie. The queftion .which 

 dtFers itfelfon \\ is occafion, is whether it could be afforded at 

 a reatonable price. 



Chromate 



