76 



THE MICROSCOPE. 



are shown in fig. 59. They are either straight or curved ; of the first 

 kind, two pairs will be required, one having the extremities broad, and 

 the other sharp-pointed ; and if large dissections be undertaken, a still 

 stronger pair, with the extremities broad, and made rough like a file, 

 will also be necessary. In dissecting under the microscope, the curved- 

 pointed pair shown at f will be found most convenient. In all of these 



.59. 



instruments the points should fit accurately together : sometimes those 

 that are very sharp are apt to cross ; this may in a great measure be 

 prevented by having the branches wide at the base where they are 

 riveted. The points can be sharpened on a hone, and a magnifier em- 

 ployed to examine if they fit closely together. 



Circular Disc. For the purpose of cutting glass covers, or making 

 shallow cells with japanners' gold-size for mounting objects, fig. 60 



fig. 60. 



will be found useful ; it is made of two circular wheels of wood, these 

 being let into a solid block of wood, and secured there by central 



