( 48 ) 
This, fays 'hlx.GerJten, is the Reafon why theMer- 
cury fails when Southerly or Wefterly Winds blow, 
and why the Quickfilver finks fo very low when thefe 
Winds blow Storm. On the contrary, fince the Effe£t 
ceafes when the Caufe is removed, the Height of the 
Mercury will be greater, the fewer fpecial Winds there 
are blowing in a contrary Dire&ion. So that the 
gentle Winds that blow from the Points of the Com- 
pafs which lie between the North and the Eaft are, 
as the Author believes, nothing but the natural and 
univerfal Motion, Current or Flux of the Atmof- 
phere impeded by or meeting with very few fpecial 
Fluxes. In order to illuftrate and confirm the Truth 
of the Demonftration of this Experiment, he hath in 
Sc hoi. i. quoted the Experiment of Mr. Hauksbee , 
in his PhyJico-MechanicalExperim. Sett. V.Experim. 
5, pag. 114. Edit. a. 
The Defign of Prop. XX is to prove, that a fpe- 
cial Wind blowing parallel to the Direction of the 
univerfal, will permit the Mercury to ftand at a great- 
er Height, than if it had blown in a contrary Direc- 
tion with the fame Force. This he confirms by 
three Obfervations of his own in the Scholium an- 
nexed. 
Proportion XXI {hows why the Defcents of the 
Q,uickfilver are fuccefiive, and do ufually, as well as 
regularly, precede the Arrival of the Winds that caufe 
them. 
Proportion XXII afllgns the Reafon why very 
confiderable Alterations in the Rife or Fall of the 
Mercury are obferved at the fame time in different 
Places, though they are at a great Difiance from each 
other. 
In 
