Of the Phenomena in 



Sometimes the Screw together with 

 the Tube breaks juft above the 

 Sucker, and the Sucker remains in 

 the Cup, of which I have alfo given 

 a Drawing : In that Cafe the in-- 

 vefting Tube clofes inftantly at the 

 Extremity of the Screw, as far as 

 it will permit, and contracts itfelf 

 nearly in a Cone, which plainly in- 

 dicates its great Elafticity in this, as 

 its Conformation to the Shape of the 

 inclofed Subftance upon the leaft 

 Change does in every other Part 



At firft View an Obferver w*ould 

 be inclined to think, that the Actioa 

 of the whole Machine is to be de- 

 rived from the Spring of the fpi- 

 ral Screw - 9 but the following Ex- 

 periments, which I tried with a 

 View of fatisfying myfelf in that 

 Particular, not only evince the Falf- 

 hood of that Suppofition, by demon- 

 ftrating that the Screw can at moft act 

 but as a Counter to a Force en- 

 tirely latent, but afford a Train of 

 Phenomena fo furprifing, that they 

 totally filenced all the Hypothefes 

 I was capable of forming. The 



Experi- 



