A RAKE BACILLUS. 45 



thorough fumigation of the lavatory and larder by means of 

 liquified SO2 (Sulphur dioxide) speedily put an end to this 

 troublesome pest. 



I heard nothing of this bacillus again until on returning 

 from my holiday a few weeks ago, when I was asked to 

 examine the water of a well supplying an important Insular 

 Institution. There seemed to me no likely reason why the 

 water should be suspected of being impure, for the well — 

 though merely a shallow spring on the hill-side- — was well 

 removed from any likely source of pollution. I asked what 

 was the reason of my being requested to make an analysis, 

 and was told that it was because the food had been " all 

 turning red "' of late, and some of the authorities thought 

 impure water was probably causing it. I asked to be shown 

 the larder, and some infected food, and instantly recognised 

 my old friend prodif/iosus. 



The authorities asked me to make a thorough investi- 

 gation of the probable cause, and although at first view 

 everything appeared to be free from sanitary defect, I found 

 that an escape of sewer gas into the refectory where the 

 bacillus first appeared was possible. In this refectory there 

 were several basins for washing purposes, connected by a 

 large terra-cotta drain to the main cess-pit of the Institution. 



Although the drain was provided with a " stench trap," 

 there was no disconnecting gulley or fresh air inlet, and thus 

 every gallon of water emptied from the basins displaced a 

 gallon of sewer air from the drain into the room, and close 

 by this drain stood the cupboard in which the bacillus first 

 appeared. The bacillus first showed itself as minute red 

 spots on some boiled pork, and from the refectory cupboard 

 it spread to the various larders of the building, and in the 

 course of a week or two it was observable on almost all the 

 cooked food, more particularly on fat salt pork, potatoes and 

 other starchy substances, and on milk puddings and cooked 

 beef. Upon analysis the water proved to be perhaps the 

 purest sample I have ever met with, and thus the only likely 

 cause for the appearance of the bacillus is the sewer gas I 

 have alluded to. 



The bacillus had resisted all ordinary methods of 

 extermination before I was consulted about it, hot water and 

 soap had been used to scrub the woodwork, and whitewash 

 had been freely applied to the walls. A long and varied 

 experience in the use of Formalin as a germicide, led me to 

 try its effects in this case, and I therefore prepared a 10 

 per cent, solution of Formalin, and directed it to be diluted 



