Journal of Applied Microscopy. 383 



the six years from 1886 to 189'2, the number of deaths due to diphtheria was 

 10,913. The chief cities of Germany present similar statistics. One-tenth of all 

 persons who die, die of tuberculosis. During recent years the mortality from 

 both these diseases has been greatly reduced, and they may now be recognized 

 in their initial stages, before serious symptoms have developed. The earlier the 

 treatment, the better the chances for recovery. In case of diphtheria, antitoxin 

 is now quite generally administered when the disease is first suspected (prepara- 

 tion of antitoxin explained). The diphtheria bacillus is probably conveyed by 

 little particles of membrane expelled by coughing and sneezing. It will grow 

 under somewhat less favorable conditions than the tubercle bacillus, but is 

 probably an obligatory parasite. The bacilli of neither of the two diseases con- 

 sidered are found in the breath. Fliigge claims to have demonstrated that the 

 danger from proximity to tuberculous persons lies chiefly in breathing the minute 

 air bubbles coughed up by the patient, and to a much less extent from the dried 

 sputa. Theobald Smith claims to have demonstrated that human tuberculosis 

 and that of cattle are not identical, although their respective bacilli bear a close 

 resemblance to each other. This authority holds that the chief danger from 

 tuberculosis lies in the intimate association with tuberculous persons and that 

 the danger from dairy products is not well founded. The tubercle germ, like 

 that of diphtheria, is probably an obligatory parasite. As yet, no specific is 

 known for the treatment of tuberculosis. In Koch's treatment it is sought to 

 produce such a condition in the body of the patient that the bacilli will be unable 

 to find suitable conditions for their growth. Drawings were presented of the 

 diphtheria and tubercle bacilli showing the different forms which they may 

 assume. — Read before the JVeiv Jersey State Microscopical Society, Feb. 27, iSgg. 



Photographic and Microscopical Section ov Franklin Institute.- — 

 At a recent meeting of the chemical section of Franklin Institute, plans were 

 made for the organization of a photographic and microscopical branch, the 

 meetings to be held the first Tuesday of each month. Lantern pictures in 

 natural colors were exhibited, H. F. J. Porter of Bethlehem showing pictures 

 taken by the McDonough method. The pictures were taken through mica screens 

 ruled 300 lines to the inch, the lines being colored alternately red, green, and 

 blue, the combination of thesecolors producing all the other colors. Fred E. Ives 

 showed pictures by the methods of his own invention of taking three pictures 

 simultaneously side by side on one plate. The three are projected through red, 

 green, and purple screens so that the images produce one picture in natural 

 colors upon the canvas. This method gives very smooth and brilliant results. 



On Keeping Medus^^ and Other Free-Swimming Marine Animals 

 Alive in Small Aquaria. — A method of overcoming the difficulties frequently 

 found in keeping free-swimming invertebrates and pelagic larvae in aquaria, 

 has been used in Plymouth Laboratory, England. It was noticed that medusae 

 in the seas simply float along with the tide, without often pulsating the 

 umbrella, and this was taken as a suggestion that slight currents in the water 



