MISCELLANEOUS HINTS TO MICRO S C OP I ST S. 199 



nished with a guide-board 5 inches long, inch wide, and |th 

 thick, and a gauge, 6 inches long, nearly | ths wide, and fth 

 thick. A card-board box, 2 by If ths, and f ths deep, to hold 

 plates of thin glass; the small brass square, already described; 

 mahogany square, 6 inches by 2J, ith thick; a number of 

 badger' s-hair pencils in handles. g z . Glazier's diamond; scratch 

 do.; marine glue (cane) brush; knife and engraver's tool for 

 cleaning cells ; small glass mules to grind the black cement on 

 the porcelain slab, and sundry glass (dropping and other) 

 tubes. g*. Pill-box with whiting; white wax for thread; cot- 

 ton-wool; sundries. 



No. 3. h. A fixed tray, 4 inches by 2 J, and fths deep, to 

 contain glass for covers to larger cells. i. A well, 5 by 4 

 inches, 1 full deep, to hold spare slides of the larger size, 

 with or without cells cemented to them, spare cells, &c. k. 

 A supply of the finest and other varieties of China three twist; 

 pill-box containing small pins, so necessary in dissecting j pill- 

 box containing cells cut in the thinnest glass. Drawer/, con- 

 tains several small palette-knives, in ivory handles, for mixing 

 the cement on the slab ; the blades differ in length from 1 J to 

 3ith, and from ith to fths at the point; drills for glass and 

 many little things. Below the shelf c c, is a similarly perfo- 

 rated shelf, raised somewhat from the bottom, the design being 

 to grasp the bottles at two points. Should the bottles not be 

 sufficiently high to occupy all the depth allowed for them, they 

 must be raised by a shelf of tin, the intention being, that when 

 the box is closed, everything should be more or less pressed 

 upon and kept in its place. The whole is japanned dead black 

 within, and lustrous black without." 



BREWSTER'S METHOD OP ILLUMINATING OBJECTS. Con- 

 sidering a perfect microscope as consisting of two parts, viz., 

 an illuminating apparatus, and a magnifying apparatus, Sir D. 

 Brewster states, that it is of more consequence that the illumi- 



