BAKER'S TRAVELLER'S MICROSCOPE. 109 



claim to "be a new invention (fig. 63), has been introduced 

 by Baker, and not inappropriately called "The Travel- 

 ler's Microscope," from its obvious capabilities. The aim 

 has been to combine steadiness with extreme portability. 

 The compound body is permanently affixed to the fore-leg 

 of the tripod-stand ; the two other legs are supported on 

 capstan-bar joints, which can be tightened at pleasure, or 

 folded up parallel with the former when not in use. The 

 difficulty of using high powers with an instrument the 

 body of which slides in cloth is well known ; the tube 

 becomes tarnished by continued use, and a firm adjust- 

 ment, which shall be easy of access, is almost indispen- 

 sable. To obtain an approximate focus, the inner tube is 

 drawn out until the combined length of the tubes is eight 

 inches; the body is then returned to its "jacket," and 

 placed at a proper distance from the stage to suit the 

 object-glass employed. The fine adjustment is effected by 

 means of a tangent-screw (fifty threads to the inch) placed 

 conveniently behind the body, and worked by a milled- 

 head acting on a spring contained in the upright which 

 supports the body. 



This part of the instrument is very satisfactory ; it is 

 steady and works efficiently. A mechanical stage is not 

 generally applied, but can be if required. Sufficient 

 movement is obtained by a plain stage, with two springs 

 to hold the live-box or glass slip. 



This microscope is carried in a leathern case 10 inches 

 by 3, seen in the woodcut (similar to that made for deer- 

 stalking telescopes), and fitted with object-glass, eye-piece, 

 live-box, &c. ; the weight of the whole not exceeding two 

 pounds in weight, and it therefore especially recommends 

 itself to the field-naturalist. 



The whole merit of this invention is due to Mr. Moginie, 

 of Mr. Baker's establishment, Holborn, who has devoted 

 much time and thoughtfulness towards bringing it to its 

 present state of perfection. 



Highley's Pocket Microscope (fig. 64), for botanical or 

 field uses, consists of a short tube furnished with a sliding 

 eye-tube, fitting into an outer tube. The coarse adjustment 

 is made by sliding the body through the outer tube, which 

 carries the object ; the fine adjustment by sliding the eye- 



