﻿480 The Philippine Journal of Science i9u 



The tubes were thoroughly shaken, and a loopful was trans- 

 planted from each tube into a test tube containing peptone solu- 

 tion. Every tube gave positive growth of cholera vibrio upon 

 transplant to a plate containing Dieudonne's medium, showing 

 that a sufficient number of cholera vibrios were inoculated into 

 each tube of water to be found in 1 loopful. The tubes containing 

 water polluted with cholera faeces were allowed to stand at room 

 temperature. Sunshine was excluded, but direct daylight had 

 free access. 



From time to time a loopful of water was subplanted into 

 peptone solution. From the time the cholera vibrio could no 

 longer be recovered in a loopful, larger quantities were trans- 

 planted. The details of the experiment are evident from Table 

 I. Plates of Dieudonne's medium were used exclusively. The 

 experiment was begun in November, 1913, and the one hundred 

 sixth day of the experiment was March 2, 1914 ; that is to say, 

 the experiment was carried on during the latter part of the cool 

 season. 



SUMMARY 



The table needs but a few remarks. It shows that the cholera 

 vibrios disappeared from distilled water first and that they were 

 evidently most numerous in the sea water. The room temper- 

 ature (25° C.) was apparently very favorable. The unexpect- 

 edly long period of time during which the cholera vibrios were 

 found alive in the tap water shows that under conditions like 

 those in tube I cholera vibrios may remain alive and multiply 

 for a considerable length of time. It is also evident from the 

 table that the vibrios remained alive in less-polluted water (tube 

 I) longer than in the heavily polluted water (tube IX). 



The theoretical possibility in the Philippine Islands of intro- 

 ducing Asiatic cholera from port to port by means of water 

 carried on board of ships and of maintaining a source of infec- 

 tion in waters polluted with human excreta thus finds experi- 

 mental corroboration. 



