FinisMng-off Slid***. 103 



gently over a spirit-lamp ; take up the cell with a pair of 

 forceps and place it on the centre of the slide, the warmth 

 of which should cause the cement of the cell to melt ; if 

 not, warm a little more, and press the cell down gently 

 with a needle point until it adheres firmly to the slide all 

 round. If the specimen is small it must be fastened into 

 the cell with some gum, as for opaque mounts, then put it 

 away until the gum has dried, apply a cover, and finish off 

 as directed for opaque mounts. Leaves of plants and 

 wings of butterflies should be mounted 011 a thin slide, so 

 that both sides may be examined. No gum will be required 

 for these specimens, but a piece of the leaf or wing should 

 be cut or punched out as nearly the size of the cell as 

 possible, and a thin cell should be used, so that the cover 

 may rest on the object and keep it flat. In all dry mounts 

 great care must be taken that all the cements used to fasten 

 the object in position are quite dry before the cover is put 

 on if not, any moisture remaining will condense on the 

 under surface of the cover and spoil the preparation. 



LESSON No. 14. 

 FINISHING OFF SLIDES- 



Canada Balsam. Quick Method. Take a small saucer 

 of benzole and a soft brush, and carefully wash away the 

 exuded balsam. Allow the slide to dry, then place it in a 

 turn-table and apply a coat of Miller's cement or Club 

 Black enamel. Let this dr-y, then wash the slide quite 

 clean with turpentine and apply another coat of cement. 



Canada Balsam. Exposure Method. Put the slide 

 into a saucer of methylated spirit, and with a small piece 

 of soft rag gently rub away the excess of balsam ; dry the 

 slide with a clean cloth and apply a coat of any good 

 cement. 



Glycerine Jelly. Put the slide into a saucer of cold 

 water and allow it to soak for a few minutes, then take a 

 penknife and carefully scrape away the jelly from the edge 



