(1244) 
Scrcr.v can always bring it in, by fcrcwing it nearer 
or farther off. 
After this manner may be feen all tranfparent Objeds, 
Dufts, Liquids, Cryftals of Salts, fmall Infefts, fuch as 
FJeas, Mites, &c. If they be Infefts that will creep away, 
or fuch Objeds as one intends to keep, they may be placed 
between the two Regijler Glajfes f. f. For by taking out 
(with the point of a Pen-knife) the Ring thatkeeps-in the 
Glajfes f f wjiere the Objeft lyes they will fall out of them- 
felves 5 fo you may lay the Objeft, between the two hol- 
low fides of them, and put the Ring. in as it was before : 
But if the Objeds are Dufts or Liquids, a fmall drop of the 
Liquid, or a little of the Duft laid on the outfide of the 
Gjafs f f, and applyed as before, will be feen veryeafily. 
As to theFirft and Second Magnifying Glaffes, being 
marked v/ith a Crofs upon the Ivory wherein they are fet, 
they are only to be ufed with thofe Regijler Plats th^it 
^ are alfo marked with a crofs, wherein the Objeds arc 
pJac'd between .two thin Taliks, becaufe the - thicknefs 
of the GlafTes in the other Regifters or Plates hinders 
the Obied: from approaching, to the Center or true di- 
flaoce of thefe Greatej: Magnifyers. But the manner of 
iifing them is the fame with the former. Only reraembef 
to be careful when you put in or pull out the Plate or Re- 
gjifter E E, whereon the Objeft lyes, or move it from one 
Qbjeft to another, not to let it rub your Magnifying Glafs, 
v/hich is done by unfcrewing a little the End 'Screw 
when ye put in or pull . out your Platen or move from 
one Objeft to another. 
For feeing the Circulation of the Blood at the Extremi- 
ties of the Arteries and /^/>//, in the tranfparent parts of 
Fidies, Eels, &c. there are two Glafs Tubes, the one big- 
ger, and the othej Jeiler, -i3.defigned in g g, wherein the 
tjih is to be put^ when this lefler Tube is ufed, ye are to 
unfcrcvv the End Screw D in the body ef^ the Microfcppe, 
until the. Tube gg can earily.en^er inta that little cavity G 
of. 
