88 The Story of the Bacteria 



into a dish of some efficient disinfectant, one 

 of the greatest dangers of the spread of the 

 disease would be removed. But unfortu- 

 nately this is in fact very rarely done. Thou- 

 sands of consumptives are walking about the 

 streets of our large towns or visiting places 

 of assembly, who discharge the infectious 

 material coughed up from the lungs upon 

 the pavements or floors. This dries, and 

 shortly is ground up, and takes its place 

 among the rest of the floating dust of the air. 

 Essentially the same thing takes place in 

 rooms in which consumptives are confined, 

 if intelligent precautions are not taken to 

 destroy or convey away the discharged ma- 

 terial. It has been found by actual experi- 

 ment that a considerable number of living 

 tubercle bacilli may be lodged, together with 

 other dust particles, high up on the walls of 

 hospital wards in which consumptives are 

 unintelligently cared for, in situations to 

 which they could haye been conveyed only 

 through the air as ordinary dust is. The same 

 material allowed to dry on handkerchiefs may 

 in a similar way become a source of danger, 



