1901 - 2 .] Plague Research Laboratory of Government of India. 123 
the tub, and in the centre is placed a similar flask containing as 
much cold water as the others do prophylactic. By means of a 
hole in the lid of the tub a thermometer is lowered into this 
centrally-placed water flask, and it is assumed that by the time its 
temperature has reached the desired height, the temperature of the 
vaccine flasks will be similar. Fifteen minutes later the flasks are 
removed and at once plunged into a trough containing cold water 
circulating through it, which rapidly cools them down to the 
atmospheric temperature, prolonged heating being one of the 
dangers to he avoided. As soon as the contents of the flasks have 
been cooled down, carbolic acid is (fig. 6) added in the proportion of 
2 ^ 0 ' the hulk of the fluid, or in other words, 0 - 5 per cent. The 
vaccine is then ready to he decanted into bottles for distribution. 
This is done in a long room contrived out of the east verandah of 
the banqueting room, by converting the arched openings along the 
side into large windows (fig. 5). This department of the work is 
presided over by another native medical man, who supervises the 
seven decanters and is responsible for all that is done in the room. 
The flasks to be decanted are kept in a sloping position by means 
of rings attached to large heavily- weighted retort stands, and 
are well elevated above the tables to admit of the adaptation of 
a glass syphon. This syphon has a portion of rubber tubing 
inserted in its length for the application of a clip to control the 
flow, and as a means of starting the syphon-action. The syphon 
apparatus is sterilised in a large autoclave under three atmospheres 
of pressure, the open ends of the tubes having been closed with 
cotton plugs in the usual way. The only part, therefore, that has 
to be sterilised by the decanter before he introduces the end into 
the flask is the outside of the tube, and this he does in a bunsen 
burner immediately before use. The syphon is started by succes- 
sively pinching the rubber tubing with a sort of milking action, one 
finger and thumb grasping it alternately below the other. In this 
way suction by the mouth is avoided, and the lower end of the 
tube is in no danger of contamination. The syphon action having 
been started, the lower end of the tube is sterilised carefully in a 
bunsen flame, and the fluid filled into the bottles held below. These 
bottles have been specially made for the purpose, and have the 
neck flush with one corner, so that no difficulty may arise in ex- 
