1884.] 



MICROSCOPICAL JOURNAL. 



199 



have kept their color for a year and 

 longer. 



Many modifications of the forego- 

 ing method have been proposed not 

 only for the primary stain, but also 

 for the agent used in decolorizing. 

 Some methods do away -with the lat- 

 ter process entirely in using a double 

 stain at the outset. Many agents have 

 been suggested to take the place of the 

 nitric acid, which I need not mention 

 here. A search through the index of 

 any medical journal for the past year 

 or two will display them all. A thor- 

 ough understanding and accurate ap- 

 plication of this method ought to pre- 

 cede any attempt at modification. In 

 the latter case the examination ought 

 to be confirmed by an application of 

 the original method to the same speci- 

 men of sputum until the modification 

 has been found entirely trustworthy. 

 — JMedical Antzals. 



EDITORIAL. 



Publisher's Notices. — All communications, re- 

 mittances, exchanges, etc., should be addre'ised to the 

 Editor, P. O. Box 630, Washington, D. C. 



Remittances should be made by postal notes, money 

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 Boston, or Philadelphia. 



Subscription price before April ist, ^i per year, in 

 advance. All subscriptions after this month begin 

 with the January number. After April ist the sub- 

 scription-price will be gi.50. 



The regular receipt of the Journal will be an ac- 

 knowledgment of payment. 



The Electric Light for the 

 Microscope. — In a short time we 

 hope to present illustrations of some 

 microscopes with the electric light at- 

 tachments, which will afford a good 

 idea of what has been done in Ger- 

 many in pei-fecting arrangements for 

 its successful use. 



The electric light applied to the 

 microscope which was shown by Mr. 

 Walmsley at the Philadelphia meet- 

 ing served to indicate the great 

 convenience of electric illumination 

 for the purpose. The lamps attached 

 to the microscope were too small- for 

 the purpose, but it will requii^e con- 

 siderable experimenting to determine 

 the most useful size. For low pow- 

 ers it was quite satisfactory, and no 



doubt would be entirely so with a 

 portable and lasting battery. This, 

 unfortunately, Mr. Walmsley did not 

 present, probably for the very good 

 reason that no such battery can be 

 obtained. 



We have since heard something of 

 a battery that has been especially de- 

 signed for this purpose,' which is eas- 

 ily renewed and not very high in first 

 cost. It measures ii by 3^ inches, 

 by 5^ inches in height, and will run 

 a lamp of 2^ candle-power steadily 

 for a considerable time. The details 

 are not yet available, but in a short 

 time we hope to give a full account 

 of experiments to test the efficiency 

 of the apparatus. 



NOTES. 



— Another stain that the histologist, and 

 especially the student of micro-botany, 

 frequently has oc casion to use is the so- 

 called indigo-carmine, or sulph-indigotate 

 of potash solution. Like the foregoing 

 (picro-carmine) the text-books content 

 themselves with recommending it, but 

 give no working formula for preparing it. 

 The following process gives a brilliant, 

 beautiful blue that works well with almost 

 any kind of preparation, and is most use- 

 ful in the double staining of vegetable 

 sections. Take of the best indigo, in 

 lump, 30 grains. Powder in a capsule, 

 and dry thoroughly in a water bath. 

 When perfectly dry, add 2 drachms (by 

 weight) of fuming (Nordhausen) sulphuric 

 acid, adding it drop by drop and stirring 

 with a glass rod. As the indigo swells 

 under this treatment, a large capsule is 

 necessary. The whole of the acid having 

 been added, stir well, cover, and let stand 

 for twenty-four hours. Transfer to a tall 

 flask, and add 3 ounces of distilled water. 

 Let stand for four days, giving the flask 

 an occasional shake. A magnificent blue 

 color is now attained, but its acidity pre- 

 vents its being used in this condition. 

 The solution must now be neutralized by 

 the addition of carbonate of potash (or 

 soda) added cautiously, with frequent 

 testings, as an excess of the alkali causes 

 the separation of the indigo in a doughy 

 mass (which can be redissolved, how- 

 ever). Filter the neutralized solution, and 

 evaporate to dryness. For use, dissolve 

 in 50 times its weight of distilled water. — 

 National DniggisL 



