670 CONDITIONS AFFECTING THE DEATH OF FUNGI. 



divided into portions of at most half a kilo in each 

 vessel, and these vessels are placed at as great a height 

 as possible, and at regular intervals. In order to pro- 

 tect the individual engaged in the experiment care must 

 be taken that the chief mass of the hydrochloric acid 

 does not gain access to the chloride of lime till the 

 room has been closed. In this way 1 per cent, per 

 volume of chlorine is obtained at first, but the propor- 

 tion very rapidly diminishes. Spores which are exposed 

 on free surfaces are killed pretty certainly, but if they 

 are surrounded by various layers of material the result 

 is doubtful. By this method, however, all sorts of 

 materials are irreparably damaged. 



Bromine is best employed in the form of masses of 

 silex, impregnated with definite quantities of bromine, 

 as recommended by Frank. These masses are placed 

 at the highest points of the room to be disinfected. 

 According to Frank, 4 grammes of bromine per cubic 

 metre are sufficient for complete disinfection, if the tem- 

 perature is kept uniformly at at least 18 C. According to 

 Fischer and Proskauer, the distribution of the bromine 

 in the room is still more unequal than that of chlorine, 

 and hence the disinfection is correspondingly more uncer- 

 tain. These experiments were, however, made at a low 

 temperature, and this probably favoured an unequal 

 distribution. Sufficient proof is still wanting that at 

 higher temperatures a really trustworthy disinfection is 

 obtained at all parts of the room. The injury to the 

 materials b} 7 bromine is at least as great as by chlorine. 



Corrosive sublimate is, as is evident from the preced- 

 ing figures, the most active bacterial poison. A solution 

 of 1 to 5,000 kills all spores in the course of some hours; 

 a solution of 1 to 1,000 has the same effect in a few 

 minutes. As such a solution can be scarcely called 

 poisonous to man, it is the best means for the disinfec- 

 tion of the hands and of numerous articles in common 

 use. It must be noted, however, that in the case of 

 many substrata, for example albuminous fluids, the 

 action may not occur, because the sublimate is precipi- 

 tated, and a sufficient quantity does not remain in solu- 



