Me 
es 
_ prevented herein by many excellent ones already publith’d by th 
| nious, Doctor Power, among his Azicrefcopical Obfervations, fave onely 
| thata quantity of Vinegar repleat with them being included in a fail 
_ Viol, and {top'd very clofe from the ambient air, all the included Worms 
_ about B, which might, perhaps, be their Gills; it feetning always the fame 
_ proportionate diftant from their nofe, from which, to the tip of their 
MicrRocRApHta, 
_ tail, C, their body feem’d to taper. 
___ Taking feveral of thefe out of their Pond of Vinegar, by the net ofa 
fmall piece of filtring Paper, and laying them ona black fitooth Gla 
_ plate, I found that they could wriggle and: winde their body, as much 
almoft as a Snake, which made me doubt, whether they were a kind of 
_ Eal or Leech. | 13b 
I thall add no other. obfervations made on this minute Anittial, being 
inges 
in a very fhort time died, as if they had been ftifled. | 
_ And that their motion feems (contrary to what we may obferve in the 
motion of all other Infects) exceeding flow. But the reafon of it feems 
plain, for being to move to and fro after that manner which they do, by 
waving Onely, or wrigling their bodys the tenacity, or ghitinoufneds, 
_ and the denfity or refiftance of the fluid medinm becomes {0 exceeding. 
« 
4 
Bich 
fenfible to their extremely minute bodies,that it is to me indeed:a gréater 
wonder that they move them (0 faft as they do,then that they move them 
no fatter. For what a vaftly greater proportion have they of their fupers 
ficies to their bulk, then Eels or other larger Fifhes, and next, the tena* 
_ city and denfity of the liquor being much the fame to be moved, both by 
the one and the other, the refiftance or impediment thence arifing to 
the motions made through it, muft be almoft infinitely greater to the 
{mall one then to the great.. This we find experimentally verify'd inthe 
Air, which though a wedium a thoufand times more rarify'd then the was 
ter,the refiftance of it to motions made throughvit,is yetfo fenfible to ve- 
+y minute bodies,thata Down-feather(the leatt of whofe parts feet yet 
bigger then thefe Eels, and many of them almoft incomparably bigger, 
fuch as the quill and ftalle) is fufpended by it, and carried to and froas if 
arhad siooweight. 20! guimatrs ni yen eerie Stet IOs 
Gis fi a j j FO ere 
veer ‘e ik f ss sd x 
Oblerv. LVIIL. Of. naw Property in the Air, and feveral ober 
~~ tranfparent Mediums nam'd Infle&ion, whereby very many con- 
» fiderable Phenomena are attempted to be folu'd, and divers oober 
J 
~ t - 
« 
| Clie the vention (and perfeéting in fome meafure) of Tele(Coper, t has 
been obferv'd = sara that the Sun and Moon neer the'Horizon, 
“are it'd ‘( lofing that exa@tly-fmooth terminating: cifcular limb, 
“which a are obiered to have when fituated teerer the Zenithy and 
ed. with an edge every way pee: upon the right ant 
217 
