84 BACTERIOLOGY. 



a very short time have little else than water containing 

 a precipitate of albumin and mercury, in so far as its 

 value as a disinfectant is concerned. 



Though the other inorganic salts have not been so 

 thoroughly studied in this connection, it is nevertheless 

 probable that the same precautions should be taken in 

 their employment as we now know to be necessary in 

 the use of the salts of mercury. 



Where it is desirable to use chemical disinfectants 

 in the laboratory much more satisfactory results can 

 usually be obtained from the employment of carbolic 

 acid in solution. A 3 or 4 per cent, solution of com- 

 mercial carbolic acid in water requires longer for dis- 

 infection ; but it is, at the same time, open to fcAver 

 objections than are solutions of the inorganic salts; 

 though here, too, we find a somewhat analogous reac- 

 tion between the carbolic acid and proteid matters. 

 Under ordinary circumstances its action is complete 

 in from twenty minutes to one-half hour. It is not 

 reliable for the disinfection of resistant spores ; such, 

 for instance, as those of bacillus anthraois. 



All tissues containing infectious organisms should be 

 burned, and all cloths, test-tubes, flasks, and dishes 

 should be boiled in 2 per cent, soda (ordinary washing- 

 soda) solution for fifteen to twenty minutes, or placed 

 in the steam sterilizer for half an hour. 



Intestinal evacuations may best be disinfected with 

 boiling water or with milh of lime, a mixture composed 

 of lime in solution and in suspension — ordinary fluid 

 " white-wash." This should be thoroughly mixed with 

 the evacuations until the mass contains a considerable 

 excess of the lime, and should remain in contact with 

 them for one or two hours. Excreta may also be easily 



