Patents connected with the Microscope. By W. H. Brown. 273 
After describing in detail the methods by which he proposes to 
improve telescopes, Dixon then describes the improvements he suggests 
for the solar Microscope : — “ A small concave mirror, diameter and 
focus at pleasure, a small hole through the middle, widest at the back 
part ; in the hole, but near the polished surface, a concave glass, to 
cause the accumulated light to fall on the object with either a small 
degree converging or paralel or diverging manner ; the objects being 
small, and on a small circular piece of black body, supported by a 
narrow bit of metal or flatted wire, very little of the light will be 
obstructed which should help to form the image. The object screwed 
until between 'the center of cavity and principal focus of the concave 
speculum, the picture would be formed at a distance according, and 
behind the real object. But to extend the magnifying power (or 
diverging of the image), and if the room is short, to answer the 
purpose of a longer room, add a large diameter speculum, form 
convex, and radius rather long ; adjust the object’s distance, and 
receive the picture on a white concave surface on one side, or beyond 
the object place or around it. A plane mirror may be used instead of 
-convex for throwing the image to side of room, Ac., or one person 
may view the image from a concave mirror of large diameter. It is 
needless mentioning the use of a concave glass instead of the convex 
or plain mirror while vision is desirable by reflection.” 
In the same specification Dixon also describes certain improve- 
ments that he has made in “ Visuals and Spectacles.” 
Adams. 
In 1797, Dudley Adams, son of George Adams, took out a patent * 
for his invention of “ Certain Spectacles upon an entire New 
Principle.” The framework of these spectacles consisted of a jointed 
and folded metal band, which encircled the head above the eyes. The 
lenses were held in a ring which hung from the band by a short rod, 
and they could thus be moved nearer to or farther from each other to 
suit different persons’ sight. 
In 1800 Adams obtained another patent t for “ A Mode of Ren- 
dering Telescopes, Perspective, Prospect, and other Optical Glasses, 
more Portable than has hitherto been Executed.” This patent applies 
more strictly to telescopes ; by his method Adams was able to make 
telescopes with more joints than had previously been made, without 
rendering them less steady. 
* Specification No. 2155, dated Jan. 23rd and Feb. 11th, 1797. Reprinted in 
1856. 
t Specification No. 2407, dated May 30th and June 21st, 1800. Reprinted in 
1856. 
1895 
T 
