592 TROPICAL HVGIEXE, SANITATION, ETC. 



After three months plough up each plot and sow with rye grass, 

 sugar cane, or tobacco. After the first crop, vegetables can 

 be grown and sent to the market for sale and consumption. 

 Swarms of flies about a trenching ground indicate improper 



management. 

 Such trenches could be dug at the base of cocoanut or palm 

 trees, a safe, effective and profitable means of disposal. 

 S ullage water should be taken to trenching grounds in special slop 

 carts where there are no good drains. 



Storm water requires surface drainage. 

 Wells must be protected and sewage controlled. 

 Dry Refuse. — This always exists in large quantities. 

 In Calcutta, with its population of three-quarters of a million, there 

 are nearly 1,500 tons daily. There are 900 carts employed making 

 three trips daily. 



For disposal incineration is always the best. 



Failing this, hollows can be filled up, covered with soil and 

 planted, but the system is not to be recommended. It should not be 

 thrown into ponds or marshes. The putrefaction, fermentation and 

 formation of gases thus produced will go on for years and mav escape, 

 proving deadly to man and beast alike, even though the refuse mav be 

 covered with several feet of earth. 



DISINFECTION. 



Disinfection is the destruction of the specific virus and is equivalent 

 to a bactericide. The term should not be applied in a general manner 

 to antiseptics which arrest or impede the growth of organisms. Dis- 

 infection means destruction of the agents of infection. 



Deodorants, of course, only oxidize and destroy or mask the effluvia. 



Much money is wasted in the purchase of disinfectants, while the 

 inefficient application of them engenders a false feeling of security and 

 often prevents simple means of purification. 



Whenever possible one should employ a simple and useful method, 

 namely, of exposing articles to direct sunlight, or rather, to the ultra- 

 violet rays of white sunlight. This is sufificient to destroy ultimately 

 most pathogenic organisms. Desiccation only will kill cholera vibrios. 



Disinfection by heat or chemicals should always be preceded by 

 thorough cleansing, e.g., stripping the paper from the walls, scraping 

 and washing the walls and floors, allowing plenty of air and as much 

 sun as possible to enter the apartments, washing, brushing, beating 

 and suspending all garments, blankets, &c. 



The chief means of disinfection are heat, hot air, steam and 

 chemicals. 



