1891.] MICROSCOPICAL JOUEN"AL. 141 



over the similarity between Koch's tuberculin and their own tiiberculi- 

 num ; but it is doubtful if one in ten of homoeopathic practitioners ever 

 prescribe tuberculinum. 



The public may at least congratulate itself that sensational journalism 

 has ceased to take much notice of the Koch treatment. This, more 

 than anything else, was responsible for bitter disappointment to many 

 sufferers. 



The most that can be said at present is : The value of Koch's method 

 is still problematical. While careful and competent men are perform- 

 ing the thousands of experiments necessary to determine its value, our 

 advice to the general practitioner is : Give your phthisical patients a cool, 

 dry climate, plenty of air, exercise, and nourishing food, and such reme- 

 dies as will best relieve urgent S3anptoms. — F. B. 



Photographs Received. — We desire to return thanks to Messrs. 

 James W. Qiaeen & Co., of Philadelphia, Pa., for the following inter- 

 esting photographs : 



Am-phipleura pellucida ; power, about i,ioo diameters; lines, 

 98,000 to the inch ; by Dr. H. J. Detmers. 



Bacillus tuberculosis; in sputum power, 1,000 diameters; bv F. 

 E. Ives. 



Co7nma bacillus of Asiatic Cholera, by F. E. Ives. 



These admirable pictures were made with the -^-^ inch oil-immersion 

 objectives, and the workmanship is excellently executed. 



TECHNIQUE. 



On the Preservation of Natural Objects in Alcoholic and 

 Other Solutions. — -The methods are simple and do not differ much 

 from the ways naturalists have ordinarily pursued for years, yet the 

 slight differences mean success or failure. 



For ffshes. Kill the fish as soon as it is taken from the water by 

 severing the vertebra near the tail. Make an incision near the vent to 

 allow gases to escape and inject alcohol through the vent and mouth. 

 Wash the fish carefully in fresh water and then place it in strong alco- 

 hol, the stronger the better, for from four to six days, until the flesh is 

 firm and all slimy matter has exuded. Then wipe the fish and place in 

 the following solution, and it will keep for years if good alcohol be 

 used : Alcohol (95 per cent.), 8 parts ; distilled water, 2 parts. 



If the fishes are small three or four days suffice to harden them, and 

 the following is a better solution for them : Alcohol, 6 parts ; distilled 

 water, 2 parts. 



Reptiles, rodents, etc., can be also preserved in the same manner. 

 The first alcoholic bath can be used over and over again, if strained and 

 kept tightly corked. 



For the preservation of tadpoles, young frogs, salamanders, and sim- 

 ilar objects, take i pound sulphate of zinc. 2 drachms burnt alum, and 

 mix well together. Dissolve i drachm of the mixture in 42 ounces 

 pure water. Filter ; let stand five or six da3-s and filter again. Speci- 

 mens to be preserved must be hardened in alcohol ; then washed in 

 clean water and left to dry until all the alcohol is evaporated ; then 

 placed in the above solution and immediately corked. 



