224 MOUNTING OF OBJECTS. 



desired, and lined witli black paper, by any pill-box maker. 

 The disks or pill-box cells may be attached to glass slides by 

 gum, so as to range in an ordinary object-cabinet; and this mode 

 will be generally adopted by such as lay stress upon uniformity, 

 and prefer the easiest methods of exhibiting their objects. As 

 there are many opaque objects, however, which can only be well 

 judged of when different sides are presented to the Microscope, 

 there is a great advantage in mounting these in such a manner, 

 as to admit of their being turned at various angles ; and this 

 may be done by attaching the disk with sealing-wax or some other 

 cement, to a pin, which may be either held between the blades 

 of the stage-forceps, or passed into the cork box at its other ex- 

 tremity ( 66). If the Microscopist should be pursuing the study 

 of any class of objects which renders it desirable to mount a 

 large number in this mode, the most convenient plan is to glue 

 two pieces of cardboard to the two sides of a piece of rather thick 

 chamois leather; one of the surfaces of this sandwich-like board 

 should be covered with dead-black paper ; and disks of any de- 

 sired diameter may then be cut out with a punch, and mounted 

 upon a pin by simply passing it through the stratum of leather. 

 The pill-box mounting will be less advantageous for this pur- 

 pose, since, if the object be completely buried in the cell, there 

 will be less power of seeing it on any but its upper surface ; a 

 pin may be secured to the bottom of such a box, however, by 

 gumming over it a piece of stout paper. Disks may easily be 

 punched, also, out of sheet gutta percha of any convenient thick- 

 ness ; or short cylinders may be made, by cutting up the thick 

 cords made for lathe-bands ; these are all readily penetrated by 

 a heated pin, and no further trouble is necessary to attach them 

 to it. Protective wells may also be made by cutting off short 

 pieces from a gutta percha tube, and attaching these to the disks 

 by a gentle heat. For the reception of boxes or disks thus 

 mounted on pins, a drawer should be provided with a thick cork 

 bottom, into which the pin is to be inserted far enough to pre- 

 vent risk of displacement. 



125. Mounting Objects in Canada Balsam. This method of 

 mounting is suitable to a very large proportion of those objects, 

 w r hich are to be viewed by transmitted light, and whose texture 

 is not affected by the loss of the aqueous fluid they may contain ; 

 and it has many advantages over the mounting of the like ob- 

 jects dry. For, in the first place, as it fills up the little inequali- 

 ties of their surface, even where it does not actually penetrate 

 their substance, it increases their transparence by doing away 

 with irregular refractions of the light in its way through them, 



tents of each box, whilst protected and kept together, are at the same time presented to the 

 eye. The Author has found the^ smallest and shallowest boxes of this kind that can be 

 made, especially when lined with black paper, extremely useful for keeping Foramini- 

 fera and other Microscopic organisms in quantities; and also for mounting larger speci- 

 mens for the Microscope as above described. 



