2108 Journal of Applied Microscopy 



r QUESTION BOX. | 



I Inquiries will be printed in this department from any inquirer. I 



I The replies will appear as received. I 



No. 27. What is Knop's solution ? 



REPLY TO QUESTION No. 25. 



In the Question Box of the Journal of Applied Microscopy for June, I 

 noticed an inquiry for a satisfactory method of mounting simple microscopical 

 objects such as fern and mushroom spores, etc. Thinking that the methods I 

 have found satisfactory for mounting fern spores and pollen of flowers might be 

 helpful to the inquirer, I will briefly describe them. I may say, first, that I 

 always keep a quantity of slides on hand all ready for use. These slides are 

 prepared by first cleaning them, then placing on a turn-table and laying on a ring 

 of gold size, thus forming a very shallow cell of the proper size for the cover- 

 glasses which are to be used. T^o mount spores or pollen, I take one of these 

 prepared slides and taking up a small quantity of glycerine jelly on the point of 

 a knife place it on the slide in the center of the gold size cell. The slide is then 

 placed on the warming table and allowed to remain until the jelly melts, when it 

 is removed, allowed to cool slightly, and a small quantity of the spores or pollen 

 stirred into the melted jelly by the aid of a needle. A clean cover-glass is then 

 taken up with a pair of forceps, held over the lamp for a few moments to warm 

 it, and placed on the slide, over the object, by bringing one edge of the cover 

 into contact with the ring of gold size at one side and allowing it slowly and 

 gently to fall into place. A spring clip is then placed on the slide to hold the 

 cover-glass securely in place, and the whole put aside under a bell-glass until the 

 jelly has hardened. I usually, if not in a hurry, allow them to remain a day or 

 two — when any superfluous jelly may be removed with a sharp-pointed knife and 

 the cover sealed down by running a ring of gold size around its edge. This, 

 when the gold size has dried, completes the slide with the exception of labeling, 

 and, if desired, finishing with ring of colored varnish. The other method I use 

 for the same class of objects is similar to the above except that Canada balsam, 

 prepared as follows, is used instead of glycerine jelly. 



Canada Balsam, 1}4 ounce. 



Turpentine, }4 " 



Chloroform, ..-.-- ^ " 



The Canada balsam prepared in this way, being liquid, requires no melting ; 

 simply place a drop on the slide, stir in the spores or pollen, and then proceed 

 as with the glycerine jelly. The only difficulty I have found with the glycerine 

 jelly is that considerable care is required to avoid air bubbles. With the Canada 

 balsam this difficulty is almost entirely removed, but a longer time is required 

 for the slides to dry so that the covers may be sealed down. 



These methods, especially the latter, I have found very satisfactory, not only 

 for the objects mentioned, but for many others, such as sections of animal and 

 vegetable substances, parts of insects, etc. L. E. Coffin. 



Center Tuftonboro, N. H. . 



