SULPHUR FUMIGATION 373 



for invaliding men who have been educated to use the latter is so heavy that 

 it would be well to adopt any measure likely to diminish it. 



In the course of the admirable work carried on in recent years in Rio de 

 Janeiro, and which has achieved such brilliant results, it has been found that 

 sulphur has given the best results in the disinfection of houses. Cruz has given 

 the following account of the method employed : 



" The house to be disinfected was completely closed. Every opening or orifice 

 where gas might escape was sealed with gummed paper. The furniture, too, 

 after being thoroughly cleansed, is tightly closed. Metallic or gilded objects 

 are protected with a covering of vaseline. After the roof is covered over with 

 canvas the garrets are opened for the free access of sulphur gas. The canvas 

 is fastened to the walls with laths. Then sulphur is burned in the proportion of 

 10 to 20 grams per cubic meter, being deposited in several receptacles dis- 

 tributed about the house and kept clear of the floor. Each receptacle should not 

 contain more than 1 kilogram (2.2 pounds) in order to insure complete com- 

 bustion. In the vacant spaces under the roof the burning sulphur should be 

 placed in receptacles set into others containing water, to avoid danger of fire. 

 After all the receptacles are placed the workmen close up the only exit left open 

 and keep the house thus sealed for not less than 2 hours. The heated air and 

 that displaced by the sulphur gas escapes through the crevices of the roof, but 

 the mosquitoes are kept in by the canvas covering." 



In the admirable fight against the yellow-fever mosquito in New Orleans in 



the summer of 1905, the following directions for fumigating with sulphur 



dioxide were given out by the health authorities : 



" Remove all ornaments of metal, such as brass, copper, silver and gilt from 

 the room that is to be fumigated. All objects of a metallic nature, which can 

 not be removed, can be protected by covering the objects tightly with paper, or 

 with a thin coating of vaseline applied with a brush. 



" Remove from the room to be fumigated all fabric material after thoroughly 

 shaking. Open all drawers and doors of furniture and closets. 



" The room should be closed and made as tight as possible by stopping all 

 openings in chimney, floor, walls, keyholes and cracks near windows and doors. 



" Crevices can be closed by pasting strips of paper (old newspapers) over 

 them with a paste made of flour, 



" The sulphur should be placed in an iron pot, flat skillet preferred, and this 

 placed on bricks in a tub or other convenient water receptacle with about an 

 inch of water in the bottom. This is a precaution which must be taken to guard 

 against accidents, as the sulphur is liable to boil over and set fire to the house. 



" The sulphur is readily ignited by sprinkling alcohol over it and lighting it. 



" The apartment should be kept closed for two hours, and then opened up and 

 well ventilated. 



" Note. — To find the cubic contents of the room, multiply the length of the 

 room by the width, and this total by the height, and to find the amount of 

 sulphur necessary to fumigate the room divide the cubic contents by 500, and 

 the result will be the amount of sulphur required in pounds. 



" Take, for example, a room 15 feet long, 10 feet wide and 10 feet high, we 

 would multiply 15 x 10 x 10, equals 1500 cubic feet. Divide this by 500 and 

 you will have the amount of sulphur required, viz. : 3 pounds." 



After a rigid series of experimental tests, Rosenau, of the U. S. Public Health 



and Marine-Hospital Service, concludes that sulphur dioxide is unexcelled as an 



insecticide. He shows that very dilute atmospheres of the gas will quickly kill 



