1900] MICROSCOPICAL JOURNAL. 249 



and it does not seem desirable to work with stronger so- 

 lutions than one per cent ; in fact the Chemische Fabrik 

 auf Aktien recommend a ten per cent solution for gener- 

 al surgical purposes. Their directions for preparing such 

 a solution are as follows : — 



"To one part of Beta-eucaine add forty-nine parts of 

 distilled water ; heat the mixture in a test tube over a 

 spirit lamp until solution has taken place, then heat to 

 boiling in the test tube, the mouth of which must be plug- 

 ged with cotton wool." This, it may be mentioned, is the 

 method whereby a sterile solution is prepared ;for zoolog- 

 ical work such precautions are unnecessary, and the one 

 per cent solution may be prepared by simple solution in 

 distilled water. 



Solutions of Beta-eucaine are said to be perfectly stable 

 in aqueous media, audit has generally been assumed that 

 aqueous solutions of cocaine are not stable. This assump- 

 tion has always appeared to me unproven, as I have had 

 solution of cocaine in plain distilled water that have kept 

 without any antiseptic for many months, and that have 

 done their work as perfectly at the end as at the time of 

 their preparation. — Annual of Microscopy. 



Photo-micrographic Notes. 



ALBERT NORMAN. 



It seems often to be thought that lime-light is essen- 

 tial to the photo-micrographer, whereas every photo- 

 micrograph can be taken successfully with a simple oil 

 lamp which may have a half-inch wick; or better still, an 

 inch wick ; or a lamp with a circular wick may be used, 

 and this latter the writer considers cannot be beaten for 

 ease in working and certainty of equal illumination, only 

 the exposure is rather long compared with lime-light. 

 Thus a specimen of bacilli magnified one thousand diam- 

 eters, which requires an exposure of one minute with a 



