DRAINAGE AxXD WATER SUPPLY 13 



water drainage, water supply, etc. The result has been, 

 as in Europe, that many of the tropical towns are vastly 

 more healthy than fifty years ago. By the segregation 

 of infectious diseases there has been a very great 

 saving in life. Cases of leprosy are now housed in 

 excellent lazarettos, and are removed from the possi- 

 bility of communicating that disease to others ; so 

 also with smallpox and other diseases. 



The growth and extension of tropical towns has, 

 of course, brought with it the drainage of the soil and 

 the swamp lands which usually existed in the earlier 

 days of colonisation. The necessity for providing for 

 the removal of storm water, and therefore the necessity 

 of making properly macadamised roads, with suitable 

 surfaces and concrete side drains, have freed many 

 towns of the puddles which formerly were the rule in 

 the rainy reason, and which are still to be found in 

 outlying villages or in the small towns of backward 

 colonies where hygiene has made little progress. 

 Therefore, with the improved drainage there has been 

 a progressive diminution of the breeding places of 

 mosquitos, and, in consequence, mosquitos are becom- 

 ing less numerous in the towns. 



Another most important factor which has tended 

 in the same direction has been the introduction of 

 pipe-borne water to the houses and to stand-pipes 

 along the roads. This has naturally brought about 

 the closing of the old-time wells, the common cause 

 of typhoid, dysentery, and cholera in the 'fifties in all 

 tropical towns. One can say that with the introduction 

 of pipe-borne water cholera has varushed, and that a 



