C 573 ) 
' rate, becaufe the Bottom of the Tube wou’d be lefs 
* prefs’d. It is plain, that the Tube mufi; be fufhciently 
‘ long, that the falling Body may not reach the bot- 
* tom before the Tube has time to rife. !n Chymical 
* Precipitations, the Veflels are either too fliort, or 
* what is precipitated falls fometimes too faft and 
‘ fometimes too flow^ for then the little Bodies are 
‘ always (as to Senfe) ift /Equilibrio with the Liquor 
* that contains them. 
‘ Monfieur Rantazzini, the famous ProfelTor at Padua, 
* to whom Monfieur Leibnitz had propoled his Expe- 
‘ riment, has made it with Succefs, after fome fruitlefs 
‘ Trials. Monfieur Reaumur (to whom the Academy 
‘ had recommended itj has alfo made it with Succefs.* 
‘ This is a new View in Natural Philofophy, which, 
‘ tho’ it depends upon a well known Principle, is very 
‘ fubtie and far-fetch’d 5 and gives us juft Reafbn to fear 
‘ that in Subjeds that Teem to be exhaufted, feveral 
things may yet efcape us. 
^mnr/{S upon Monfieur Leibnitz’^ 
principle. 
Figure 4. 
L et a B be the Bottom of a Veftet full ©f any 
Fluid, whole Top is either wider than the Bot- 
tom as GH, narrower as EF, or equal to \t as CD. 
The Preflure of the Fluid upon the Bafe AB will be 
equal to the Weight of CB, or of a Cylinder or Prifm of 
the fame Fluid, made up of the Area of the Bafe multi* 
plied into the perpendicular Height above it. 
Jf the Fluid be equally dcnfe every way as Water, 
or of a Denftty uniformly diminifh’d as you go upwards* 
this Propofition (call’d by Mr. Boyle the Hydroftatical 
T t t c Pa- 
