92 



THE AMERICAN MONTHLY 



[May,' 



enjoyable, and it is really very easy to 

 make good negatives by lamplight. 



As for the printing on paper, I 

 would not advise amateurs to under- 

 take to tone and fix his paper 

 prints. It is a more or less trouble- 

 some operation, and requires some 

 experience to do it well. Sensitized 

 paper can be bought in sheets, and it 

 is well enough to get a printing frame 

 and to do the printing if one has 

 time, for the microscopist can print 

 from his own negatives better perhaps 

 than an experienced photographer 

 who is ignorant of the special features 

 to be brought out. But the subse- 

 quent processes of toning and fixing 

 had better be entrusted to practical 

 photographers who are prepared to 

 do much better. 



There is a small, but very useful 

 and practical book which I can re- 

 commend to anyone who desires to 

 learn the details of making dry-plate 

 negatives — ** The Photographic Ama- 

 teur," by Mr. J. Trail Taylor, who 

 has kindly volunteered his valuable 

 assistance in making a negative this 

 evening. This book was written 

 especially for amateurs in field photo- 

 graphy, but it contains all the in- 

 formation the microscopist will re- 

 quire, and it is sold for half a dollar. 

 o 



Hints to Amateur Microscopists. 



BY REV. W. S. FALKINBURG. 



I presume that one, at least, of the 

 almost imperatively necessary quali- 

 fications of a microscopist is ingenui- 

 ty. When one is a thousand miles 

 from the manufactory of accessories, 

 or when, if he were within one square, 

 on account of the lack of the " root 

 of all evil," he is unable to purchase 

 what he needs, a friend helps him to 

 make it for himself, or helps a near 

 neighbor to do it for him, I think it 

 certainly is the act of " a friend in- 

 deed." I have the misfortune to be- 

 long to the class whose "ship has not 

 come over," and as the family of 

 these is large, let me tell how I im- 

 provised an excellent bull's-eye con- 



denser, hoping that I may help some 

 brother microscopist. 



First I cut a disc of sheet-tin, 2 

 inches in diameter. Then, using a 

 piece of French plate-glass (as thin 

 as possible), I cut it, as near the size 

 of the tin as I could, with a steel-disc 

 glass cutter ; then, with a pair of 

 scissors held unter water, I cut the 

 glass to the exact size and shape of 

 the tin, then ground the glass upon a 

 grind stone, until it was round and 

 smooth. Then, taking an old-fash- 

 ioned bull's-eye watch-crystal, such 

 as watchmakers have, I ground the 

 side that would be next to the face 

 of the watch, until it laid perfectly 

 flat and snug upon the plate-glass. 

 Then, after carefully cleaning the 

 glasses, filled the crystal with warmed 

 glycerin, and covered it with the plate- 

 glass, just as we drop the cover upon 

 a slide, so as to enclose no bubbles. 



Then wipe off the overflowing gly- 

 cerin and cement the edge of the 

 crystal with gold-size. 



I then made a cell of sheet-brass, 

 but a blacking box of the right 

 size will answer. Solder a tin 

 or brass tube to the side of it. Fit 

 a ^-inch wire into the tube. Let the 

 wire pass through a cork placed upon 

 an upright rod, and fasten this into a 

 solid foot, and it is complete. 



My condenser is a plano-convex, 

 i^ inches diameter and of 3 inches 

 focus. 



I have painted the brass and other 

 work, and have used it daily to per- 

 fect satisfaction. 



Greenwood, Ind. 



Double Staining with Carmine 

 and Anilin Green. 



The preparations used by the 

 writer for the above process are 

 those recommended by Geo. E. Da- 

 vis, F. R. M. s., in his work, " Practical 

 Microscopy," just issued. 



The formula for the carmine stain 

 is: carmine, 15 gr.; ammonia, 15 gr.; 

 distilled water, 2 oz.; dissolve car- y 

 mine in ammonia over the flame of a 



