1892.] THE MICKOSCOPE. 203 



Assuming the mount to be a section of vegetable tissue, the steps 

 involved in its preparation w^ould be the cutting, staining, wash- 

 ing, and dehydrating. The length of this article will not permit 

 any reference to cutting, so the process of staining is next noticed. 

 Any stain insoluble in the glycerine may be used. It is best 

 applied immediately after the cutting of "the section. After the 

 section has acquired the proper depth of color, it should be 

 thoroughly washed and then placed in glycerine. From here it 

 goes through the next process — placing in the cell. 



In placing the section care should be exercised to have it ex- 

 actly in the centre of the cell. With the section thus situated a 

 drop of glycerine is allowed to fall upon it from tlie dropping-bot- 

 tle. Take the clean cover-glass between the left thumb and fore- 

 finger and place the left side in contact with the drop of glycerine ; 

 draw it over until supported on the left edge of the cell-wall ; 

 loose the hold of the left hand and allow the cover-glass to fall 

 gradually by supporting the right edge with a needle. Having 

 thus jDlaced the cover- glass and centered it, place a clip upon it. 

 The superfluous glycerine thus forced out is washed away by 

 means of a jet of water from the wash bottle so directed as not to 

 strike under the cover-glass. Some water does get under, but this 

 does no harm, as it supplies moisture which the glycerine other- 

 wise would have by "' creeping" from the cell. 



When thoroughly dried by means of strips of bibulous paper 

 the slide is ready for the last step — securing the union of cover- 

 glass and cell-wall. 



This result is best obtained by ringing once around the cover- 

 glass and allowing this coat to dry before applying cement 

 enough to hide the junction of the cover-glass and cell-wall. 

 When this latter step is accomplished the mount is essentially 

 complete, but no one who has a pride in his work will leave the 

 slide unstriped. There is no more beautiful slide than one 

 formed of white cement and ringed with black. Properly labeled 

 and cleaned, the slide is ready for the cabinet ; and if the due 

 amount of care has been exercised in its preparation it will al- 

 ways be a source of pride and pleasure to its owner. 



Mode of Keeping Fresh-Water Animals Alive. — Dr. J. 

 Dewitz recommends the spreading of a piece of canvas or small 

 dampened towel over the bottom and side of a plate on which 

 the fresh-water animals are placed. They must then be covered 

 with another wet towel and put in a cold room. The towels 

 must be washed and wrung out every fourth day, and any dead 

 specimens removed. — your. Royal Micr. Soc.., London^ yutie., 

 1 8^2, 



