98 



The Microscope. 



to be placed within four circular perforations in a piece of paste- 

 board forming the centre of the slide; and a brass fish-plate, an 

 almost invariable accompaniment of microscopes of the last 

 century, which was used for confining a small fish, in order to 

 exhibit the circulation of the blood in its tail. 



To the bottom of the drawer is afiixed a paper, on which is 

 written, in a neat hand, the following inscription, with difl&culty 

 decipherable : 



Audax Japeti genus 



Ignem fraude mala gentibus intulit 



Nil mortalibus arduum 



— Hor. Carm. Lib. I. 3. 

 In perpetuam memoriam consuetudinis quam cum dulcissimo 

 suo sodali Carolus Linne Parisiis habebat hoc ab eo amicitite donum 

 accepit Mense Augusto MDCCXXXVIII. 



Bernaedus Jussieu. 



The instniment stands sixteen inches high, and can be extended 

 by means of a draw-tube. The stand is of wood. The body-tube, 

 of pasteboard, ornamented with embossed paper, is clamped near its 



lower extremity to a horizontal brass 

 bar, which is fixed at its opposite end 

 to a grooved plate sliding upon a verti- 

 cal brass post, focusing being effected 

 by means of a screw, a modification 

 of the form introduced by Marshall, 

 about 1704.* 



The accessories, in addition to those 

 already described, are a double mirror 

 beneath the stage, one face being 

 slightly concave and the other plane; a 

 holder for a "bulls-eye" condensing 

 lens, from which the lens has dis- 

 appeared; and a circular ebony disk, 

 mounted on the end of a brass rod, one 

 of the faces of the disk being inlaid 

 with ivory, the object of this device 

 apparently being, as described in old works on the microscope, to 

 exhibit opaque objects; "light colored ones are to be stuck on the 

 dark side, and vice versa." 



* Mayall : Cantor Lectures on the Microscope. 



