Patents connected with the Microscope. Bij }V. H. Brown. 259 
Lindsay (pi. IV.). 
The next specification referring to the Microscope is No. 588,* * * § 
dated the 17th February and the 1st and 4th June, 1743. It refers 
to a portable Microscope made by George Lindsay. I am pleased to 
say that the Society possesses two examples of this Microscope. One 
of these instruments is a very complete specimen ; the other wants 
many of the principal parts. One of Lindsay’s Microscopes was 
exhibited at the International Exhibition held in London in 1876. 
The instrument was first noticed by later writers in 1878, f and atten- 
tion was again directed to it by the late Mr. John Mayall, in his Cantor 
TLectures, J but it does not appear from either of these notices that the 
patent was ever examined. The figures in the German publication 
were probably taken from the instrument and not from the specifica- 
tion, as stated in the Journal. § The title of the specification reads : — 
“ Whereas His Majesty, by His Letters Patent . . . dated the seven- 
teenth day of February, in the sixteenth year of His reign, did grant 
unto me, George Lindsay . . . the sole use and benefitt of making 
and vending 4 A Generali Portable Microscope, of a Structure intirely 
New and Different from any now in Use, which, with Parts for 
Transparent and Opake Bodies, Conveniences for Living Creatures, 
^nd a Stand and Deflecting Speculum, are contained in a Case not 
exceeding Six Cubick Inches, and is so contrived as the Instant it is 
taken out to be Beady for Use, without the Trouble of Screwing and 
Unscrewing any Part, and Measures by a Scale the Focall Distance 
of each Lens, thereby giveing the Beall and Apparent Magnitudes of 
Objects, having also Deflecting Mirrors for Illuminating Dark Bodies, 
and is applicable to all the Purposes which the Nature of Microscopes 
admitts.’ ” 
In the Library of the British Museum there are two copies of a 
Tather scarce pamphlet by Lindsay, entitled, 4 An Explanation of the 
Mechanism and Uses of a general portable Microscope, first invented 
;and made in the year 1728 ; and Publish’d by His Majesty’s Boyal 
Letters Patent, February 17, 1742. By George Lindsay, Watch- 
maker in the Strand, London.” The date 1742 is evidently wrong, 
as the specification gives the date 1743 ; while in both the letter of 
patent and the specification the sixteenth year of the reign of 
George II. is given, which is also 1743. I may here state that both 
the Society’s instruments bear the date 1742 ; one of them is num- 
bered 22, the other does not appear to have been numbered. As 
Lindsay’s Microscope is so rare, I venture to quote the description 
of it from his pamphlet ; the illustrations are taken from the dia* 
* Reprinted 1856. 
f Bericht fiber die wissenschaftlichen Apparate auf der Londoner Internat. 
Ausstellung im Jahre 1876 (Achenbach und Falk), 1878, part i. pp. 52-3 (2 figs.). 
See Journ. R.M.S., 1883, p. 70S (2 figs.). 
X The Microscope, Journ. Soc. Arts, xxxiv. (1886) p. 1048, fig. 52. 
§ 1887, pp. 293-4 (1 fig.). 
