T ) 
a fmall fpace of Time (fufficient for it to fubfide fo the 
bottom) I viewed both the dry piece and the wet with 
a Microfcope, and how nicely foever I obferved them, I 
could not difcover that the parts of the one were thicker 
than the parts of the other. 
Moreover, I viewed again the parts of the Spunge as 
exadly as it was poffible for me to do it, but I could ne- 
ver difcover that there was the leaft Concavity in fhe 
flender parts thereof, for if there were any Concavity in 
them, I conceive it would appear when I examined thofe 
fine parts with my Microfcope; For my farther fatisfafti- 
on J prepared a Glafs Tube that was flenderer than one of 
the Particles of the Spunge, and was withal hallow, and 
I placed the fame before a Microfcope, having putafmall 
Drop of Water into one end of it, and then I viewed it 
again, at which time it appeared clearly to me (as I have 
feen feveral times before) how far the Water was come 
into the Tube, for where the Water is, there the Glafs 
appears as a folid Body 5 whereas on the contrary, in a 
Giafs that is hallow, the Concavity alone is only Tranf- 
parent, but the fides do not appear fo Tranfparent, 
After this I endeavoured to divide the exceeding flen- 
der parts of the Spunge lengthways, becaufe I do con- 
clude that flender parts have no ftrength unlefs they are 
composed of yet flenderer parts, which was very difficult 
for me to do, becaufe they are fo ftriftly united to each 
other 5 however I was fufficiently convinced that the faid 
flender parts do cortfift of yet much finer. 
n. 
