The Microscope. 185 



I have also mentioned the formula of a comparatively new stain- 

 ing process, which I think is more rapid and simple than any I 

 have seen generally published. 



The tubercle bacilli are about half the diameter of a red blood 

 corpuscle in length, so a good power is required to see them ; at 

 least a one-sixth objective, a good eye-piece and condenser are 

 necessary. Strong white light should be selected, such as that 

 from a north window or a student lamp. 



To collect or to keep sputa it is not necessary to use bottles. 

 Ordinary paper pill boxes of large size painted inside with two 

 coats of shellac will answer all requirements, and can be mailed, 

 if necessar}^ or destroyed by fire and cost but little. To keep 

 sputa for several days, add a few drops of a ten per cent, solution 

 of carbolic acid. 



The first sputum expectorated in the morning, is the best to 

 examine. First hold a needle (an ordinary needle stuck in a 

 small stick will do), in an alcohol flame until red, then cool and 

 with the point pick up a small bit of sputum. The white lumps 

 are the best to select for this purpose. Spread the sputum as 

 thinly and evenly as possible on the cover glass and let it dry 

 in the air, then take it in forceps by one corner and pass it 

 through the top of an alcohol flame, sputum side up, three times 

 with the pause of a few seconds between each time; pass it 

 through the flame about as fast as one would cut bread. It is 

 now ready to go into the staining solution. The following stain- 

 ing and decolorizing solutions are now quite largely used in Ger- 

 many and were shown to me by Dr Prudden of New York, 

 and after having used them almost daily for four years, I can 

 jecommend them as practical and rapid, provided fine dyes are 

 used, such as made by Prof Grublers. These can be obtained 

 ;at Meyrowitz Brothers, 23d Street and 4th Avenue, New York. 



Sol. No. 1 — Fuchsin, 15 grains, 



Alcohol, 2 drams, 



Carbolic Acid, 1 " 



Water,.. 2 ounces. 



Add the alcohol to the fuchsin and shake well until it is dis- 

 selved, then add the carbolic water. 



Sol. No. 2 — Methyl-blue, 15 grains, 



Sulphuric Acid, C. P., 1^ ounces, 



Water, '. l.l ounces. 



