the Cultivation of the Bacillus of Tubercle. 



189 



the fluid collected, the average "being 0*4. Hence, by calculation, 

 we obtain the rough estimate that about 3 grs. of organic matter is 

 given off from a man's lungs in the course of twenty-four hours. 

 Doubtless a very small amount, but sufficient to render the aqueous 

 vapour thus thrown off more impure than most sewage water, and 

 ample in quantity, to foster the growth of organic germs. 



It was the result of this research that induced me to try to culti- 

 vate the bacillus of tubercle upon these and similar organic fluids, 

 such as were likely to be met with in dwelling-houses. 



By means of a simple freezing mixture of ice and salt it was easy 

 to condense the aqueous vapour, both of the breath and that coming 

 from ground air; and, in order to make the inquiry more complete, 

 the vapour of the breath was collected in a flask, surrounded by this 

 mixture, from both healthy and diseased sources. In other words, 

 both healthy persons and those affected by phthisis were prevailed 

 upon to breathe into the flask, until a sufficient quantity of aqueous 

 fluid had been obtained. 



With another apparatus, consisting of a framework supporting 

 beakers containing freezing mixture, collections of aqueous fluid 

 Were obtained from "ground air" coming from a wine cellar in a 

 gravelly subsoil, and from cellars under several low-lying, unsanitary 

 cottages in Southampton. Some of the moisture from a weaving- 

 shed in Blackburn was also thus collected and used as a culti- 

 vating medium. The composition of these latter fluids is given 

 below : — 



Table I. — Composition of condensed Aqueous Vapours from 

 following sources. 



Sources of fluids. 



Parts by weight of 

 ammonias per 100,000. 



| 



Grains per gallon of 

 ammonias. 



Free and 

 saline. 



Albuminoid. 



Free and 

 saline. 



Albuminoid. 





1 -622 



3 -568 



1 -135 



2 497 





0-973 



2-598 



0-681 



1-S16 





0-649 



1-622 



0-454 



1 -135 





2-341 



3-893 



1 -498 



2-724 





0-020 



030 







Blackburn weaving sheds 



0-319 



0-082 



0-223 



0-057 



(average) (humidified) 











Thames sewage at South 



2-309 



3-893 



1 -498 



2-724 



Outfall (Keats) 











These several liquids were carefully sterilised by repeated boilings, 



