46 now TO WORK 



tearing or unravelling various tissues, in order to display their 

 elementary structure, and for separating any minute object from 

 refuse or extraneous matter, previous to its being mounted. Very 

 thin needles are useful for separating substances under the field of the 

 microscope. Needles which have been flattened at the points, and 

 subsequently hardened, tempered, and sharpened on the two edges, 

 make capital knives for very delicate work, or the pins used by the 

 surgeons and termed harelip pins may be used with advantage. They 

 may be inserted in a small wooden stick, fig. So, or held in the handle 

 of a crotchet needle. Mr. Matthews has lately made some needles 

 with cutting edges, which are very useful for making minute 

 dissections. 



81. Forceps. A pair of thin brass forceps will be found con- 

 venient for applying the thin glass cover after the preparation has 

 been placed upon a slide or in a cell. A pair of dissecting forceps 

 are also required by the microscopist. One pair should be strong 

 with straight limbs, the other pair should be small, with thin curved 

 blades, terminated with somewhat rounded points, having very flat 

 but slightly roughened surfaces of the pattern represented in 

 pi. XV, fig. 85. 



Forceps for holding minute objects under the microscope are 

 made to fix upon the stage, fig. 86. 



Leaves and feathers and other flat objects can be examined by 

 being placed flat on a glass slide or in the stage forceps. Mr. James 

 Smith has invented a leaf-holder, which may be useful to those desir- 

 ing to prosecute particular researches in this direction with low 

 powers. This instrument is described in the Microscopical Jour- 

 nal for July, 1866, p. TOO. 



82. Wooden Forceps made of box-wood, with broad ends, are 

 convenient for holding the glass slides when hot, for if held with cold 

 metal forceps, they often crack. The same object may be gained 

 more simply by fastening to the limbs of an ordinary pair of forceps, 

 flat pieces of cork. Modifications of the simple spring clips described 

 in p. 52 may be used for the same purpose. 



The different instruments above referred to may be obtained 

 packed in a case, of Mr. Collins and Mr. Highley. They are all made 

 by Weedon, of Hart-street. 



Glass Slides, thin Glass, IVatc/i-g/asscs, Glass Shades. 



83. Plate Glass slides, the edges of which are ground and 

 polished, may be obtained ready for use at six shillings per gross, or 

 they may be easily cut out with the diamond, and the edges ground 



