( so 10 ) 
to the weight of the Air, which preffing upon the water of the 
veflfel makes it rife in the fiphon^ whilfl: on the other fide it 
defeends by its weight ; M.Hugens found a means to make the 
water of the fiphon run, after that the Recipient was exhau- 
ftedofAirj and he fa w, that with Water 
* jvf.Hugens huth mude purged of Air * it did the tffcO: as well as 
t^TX^^sn'n Without the Recipienr. The fliorteft of 
conffiend.aiwtiiwith thc legs of thc fiphon was eight iuchcs 
VJ^ma^withUtxcM' iQj^g^ its aperture, of two hues. And 
' he will not have us doubt, whether the Rer 
cipient was well exhaufted of Air ^ for he did aflure himfelf of 
that, as well by finding that there came out no more Air 
through the pump, as by other morece^rtain marques. 
And this he takes for a further confirmation of his fuppofi* 
tion of a preflSng matter more fubtile than the Air* To which 
he adds, that, if you take the pains of fearching, to what de- 
gree the force of this preflure reacheth, (which he faith can- 
not be better made than by purfuing the Experiment with 
Tubes full of Mercury yet longer than thofe employ'd by M. 
Boyle^) it will perhaps be found, that this force is great enough 
tocaufethe^»/(>« of the parts of Glafs and of other forts of 
bodies, which hold too well together as not to be conjoyned 
but by their contiguity and reft,as l\,DeSi€arUs would hare it. 
JnExtraB 
