58 THE AMERICAN MONTHLY [Feb 



Wash well in methylated alcohol until no more red color 

 comes away ; rinse in water, and, still holding- the cover 

 slip with the forceps, drop a watery solution of methylene 

 blue upon the film and allow it to stain for thirty seconds. 

 Drain off the stain, wash rapidly in water ; press gently 

 between folds of blotting- paper, and allow it to dry in the 

 warm air above the flame at such a height that the hand 

 can be easily held there. Mount in xylol balsam. Tuber- 

 cle bacilli will be stained red by the fuchsine ; all other or- 

 ganisms will be colored blue. A very convenient and use- 

 ful method for the preliminary staining and examination of 

 any smear preparation, is to mount it, when fixed, in a drop 

 of Loffler's methylene blue and remove all surplus stain 

 by gently pressing a piece of blotting paper upon the 

 specimen. Microbes, cell nuclei, etc., take upthe dye very 

 readily, and show up well although mounted in the dye 

 itself, which in such a thin film appears almost white by 

 contrast. 



Baker's Number One, D. P. H. Microscope. — Mr. Chas. 

 Baker, London, has adopted the lever form of fine adjust- 

 ment, which, origially so adversely criticised, has now 

 justified its existence as being- one of the most delicate, yet 

 steady and reliable ad j ustments made. The form of tripod 

 foot is steady and gives more room than usual for the ad- 

 justment of the under stag-e arrangements. The micro- 

 scope is fitted with the usual focussing and centering sub- 

 stage, swinging tail-rod of mirrors, draw-tube, etc., and 

 with addition of theexcellent mechanical stage costs $53.25. 

 Without this last, but with the Nelson type of horse-shoe 

 stage, fitted with sliding bar, the microscope costs $42.00. 

 This instrument can be strongly recommended both for 

 workmanship and design, for all purposes of original re- 

 search. 



Cement for Glycerine Mounts. — In making permanent 

 specimens of objects mounted in glycerine or Farrant's 

 medium, considerable difficulty is experienced in cement- 

 ing the cell. I have tried various methods, but the most 

 successful in my hands has been to use a thick solution of 



