ZOOLOGY AND BOTANY, MICBOSCOPY, ETC. 



517 



and from nose-piece to field-lens 4 in. The concave mirror is L| in. 

 diameter and :>.j in. focus ; there is no plane mirror. The pillar is 

 9^ in. in length, from top to centre of rale-joint, and is ^\\n. square in 

 section. The limb, or arm, is fixed ; the centre projecting 1 i\. beyond 

 the pillar. 



Granger's Pocket Microscope. — The Society is indebted to a 

 Member of the Qnekett Microscopical Club, who desires to remain 

 anonymous, for this interesting little pocket Microscope (fig. 77). The 

 donor writes that it was given to the person from whom he obtained it 

 some thirty years ago, or more, by one of the Grangers, who were a 

 family of lawyers. On the underside is engraved the following : — 

 "B. Granger, Tettenhall, 1790." 



This little object seems to have been a forerunner of the modern 

 pocket magnifier. It is a sort of mult am in parvo, for, besides an 

 arrangement for viewing an object impaled on the point of a needle, it 

 contains two other magnifiers, one of which is packed away within the 

 mount of the other. The inner magnifier has an arrangement for 



Pig. 77. 



containing a minute living or other object between two glasses, one of 

 which is concave. The lenses are all of very low power. 



In this connection it may be mentioned that among the apparatus 

 belonging to the Pritchard Microscope exhibited at the June Meeting by 

 Mr. Holder, was an object that no one could then understand. It is 

 evidently part of a similar box of magnifiers. The lens and needle for 

 viewing opaque objects, and the bottom cover, are missing, and the 

 inner magnifier is different, for, instead of the arrangement for con- 

 taining a live or other object, it is fitted with a second lens, thus 

 increasing its magnifying power. - r.*B| 



These two specimens have been shown to Mr. Nelson, who says he 

 has seen several similar to them, but they were made of ivory. 



In the figure, A represents the brass box closed. B represents the 

 dome C removed, and shows the arrangement for viewing an object 

 fixed on the point of the needle. E is a magnifier formed of the central 

 part or body of the box, the top and bottom covers being removed. It 

 has a lens of low power mounted at the upper end. The magnifier D, 

 which has a lens at its upper end and a live-box at its lower end, goes 

 inside E when the box is closed. 



