INFECTIOUS DISEASES AND MICROBES, ETC. 241 



made from it at any time during a period of five 

 months. If, however, instead of keeping it dry and 

 in the dark, fragments of these membranes are 

 exposed to the light and moistened and desiccated 

 alternately, the virus is destroyed much more 

 rapidly. From all this, and from the fact that the 

 bacillus is destroyed by moist heat at 58 C., it is 

 evident that by far the best method of disinfecting 

 clothes, the floor, the walls, and furniture, is by the 

 use of a liberal supply of boiling water ; for although 

 a temperature of 98 C. (dry), continued for an hour, 

 is necessary to destroy the vitality of the bacillus, 

 moist heat at a very much lower degree (acting only 

 for a minute or two, according to the temperature), 

 is sufficient to disinfect everything on which it is 

 allowed to act ' (Woodhead). 



Drs. Behring and Kitasato 1 have recently dis- 

 covered a method of producing immunity against 

 diphtheria. As this is similar to Kitasato's method 

 of treating tetanus, which has been already described 

 (see p. 214), no further remarks are needed. 



'Antiseptic throat washes, 2 not merely gargles, 



1 Deutsche Medicinische Wochenschrift, 1890, p. 1113 ; and 

 Zeitschrift fur Hygiene, 1890-1. 



2 The following is an excellent antiseptic throat wash : 



IJ. Potass, chlor. pulv. , 3 ij. 



Acid hydroch. fort, 3 j. 



Let stand mixed for 10 minutes, 



then add water gradually shaking 



each time to . f . 5 vi. I 



Syrup, . . f.5j. { 



To be used with a spray apparatus or syringe. This fluid not 

 only loosens the diphtheritic membrane, but also destroys the 

 bacilli. 



