Patents connected ivith the Microscope. By W. II. Brown. 261 
as represented in Fig. 3, to another which draws out of the Slider- Case 
P. The Body of the Fish, Frog, &c. is to be laid on the Plate S, and 
gently tied down, the Tail or Foot being extended over one of the Holes 
in the other, and may he confined from moving, by a little Plate* with 
two holes in it, represented underneath, that puts on at the end. The 
Creature thus fixed, .put the Plate with the Holes into its Place in the 
Slider-Case, and open the Object-Part, by loosening the little Nut d , 
then bring the Place you would view before the Aperture, and holding 
the Object-Part together, fix it fast by tightening the Nut ^examine it 
with the fourth or fifth Magnifier, and you will see the Blood Globules 
rolling through the Veins and Arteries with a prodigious Bapidity . . . 
“ Of viewing Opake Bodies. These, if they are whole Insects, may 
be taken in the Tongs 0, and the instrument is immediately made fit 
to receive them, by drawing of [/] the Brass Plate of the Object-Part, 
and turning down the other, which being confined by placing the little 
Nut d, as represented in Fig. 2. There will be a Cavity at e fitted to 
receive the Tail of the Jointed Bar N, in the Spring Tube of which you 
are to put the Needle 0, and present your Object before tbe Aperture. 
If it be pretty large, the first Magnifier is proper. This is set in one of 
the Silver Mirrors V, and goes into the Groove as the Sliders G G . . . 
If you find it necessary to magnify more, you must use the other Mirror 
T, which has a Mark on it at/, to show the Way it is fitted to go on 
the Outside of the Groove before mentioned . . . the 2nd, 3rd, and 4th 
Glasses are to be used with it.” 
After describing the box, Lindsay gives the following instructions 
how to use his instrument as a solar Microscope. He says, “ The Use 
of it depends on the Sunshine, and there is an Apparatus which is 
Fig. 41. 
commonly made to fix to the Window-Shutter, consisting of a Tube, a 
Convex Lens and a Looking-Glass ; at the end of the Tube there is a 
small Tube to fix on the common Pocket Microscope , and the Instru- 
ment describ’d in this account is capable of being apply ’d and fix’d to 
this Tube, and used with less Trouble. Fig. 2 [fig. 41] in Plate 2 f 
* This plate is missing from the Society’s instruments, 
f This figure is taken from the pamphlet. 
