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VL An Account of a Book, intituled Chriftiani 
Ludov.GerftenTentaminaSyftematisnovi 
ad mutationes (Bamnetri ex natura ek- 
teris aerei demonftrandas, cui adje&a Tub 
finem, Diflertatio Roris decidui errorem 
antiquum Sc vulgarem per obfervationes 
Sc experimenta nova excutiens. Fran- 
cofurti MDCCXXXiir, in 8 W - 
I Shall not here give any Account of the various Hy- 
pothefes, which have been invented by the Learn- 
ed, to folve the feveral Phenomena of the Barome- 
ter, and to explain the Changes of the Weather con- 
fequent upon the Rife and Fall of the Mercury, 
but refer my felf to the ingenious Author of this Ef- 
fay, who alfo propofes a new one, drawn from the 
Nature of the Elafticity of the Air, and delivered 
after the manner of the Geometricians. 
The Effay itfelf confifts of three Chapters ; the 
firft is wholly Mathematical, containing a new The- 
ory concerning the Propagation of tremulous Vibrati- 
ons along a Series of contiguous elaftic Bodies. The 
fecond applies this Theory to the Solution of the 
chief Appearances of the Barofcope, and the laft 
explains the feveral States or Conftitutions of the 
Air and Weather connected with them. 
F x To 
