C i8 3 3 
do it, without the Affiftance of many Figures, nor 
without the Mention of feveral other Fads, that I 
have not yet fufficiently fatished myfelf about, nor 
obferved fo often as I think it neceffary to do. 
I (hall alfo endeavour to carry on further the 
Natural Hiftory of all the feveral Polypi of which I have 
yet fpoken, and, perhaps, that of tome other Sorts 
befides ; as I find, that the Experiments I make upon 
Infects of one Species, facilitate in feveral Refpeds 
thofe I have to make upon others ; and that thefe 
laft often throw a new Light upon Obfervations and 
Experiments already made. 
As all thefe little Animals are exceedingly minute, 
I have hardly been able to obferve any of the feve- 
ral Fads above-mentioned without the Affiftance of 
the Microfcope 5 but, if I was to take fuch fmall 
Objeds out of the Water, in order to expofe them 
to my Glaffes in the common Way, I fhould both 
rifque the lofing of them, and hazard the putting 
them out of a Condition of performing their natu- 
ral Operations. I am therefore forced to obferve 
them with the Magnifiers of my Microfcope, without 
taking them out of the Glaffes I keep them in. I, 
for this Purpofe, contrive to get them fo near the 
Sides of thofe Glaffes, that the Foci of my Magni- 
fiers may reach them from without: I then fix, by 
the Sides of my Glaffes, a jointed Arm I have fitted 
for that Purpofe, into the Socket of which I can 
conveniently ferewthe different Magnifiers of my Mi- 
crofcope, and retain them fixed at their due Diftances, 
by which I am able, with great Eafe, to keep the Ani - 
malcula in Sight as long as I have Occafion for them : 
and I ufe for the mold part the Light of a wax Taper, 
to illuminate my Objeds. 
A a 
XL 
