594 TROPICAL HYGIENE, SANITATION, ETC. 



(3) It should be soluble and emulsible in water. 



(4) It should not produce injurious effects on human tissue. 



(5) It should not be too costly in proportion to its germicidal value. 



(6) Heating "should not affect it. 



Corrosive sublimate is poisonous, acts on metals, is thrown out of 

 solution by alkalies and organic matter, is acted on by oxides, sulphur 

 and sulphuretted hydrogen, loses its efficiency when mixed with 

 sputum, faeces, &c., because a harmless albuminate of mercury is 

 formed. Its use is therefore limited. It is usually mixed with other 

 chemicals to overcome some of these difficulties. 



Carbolic acid is not so widely used as in former times because its 

 bactericidal power is sixteen times less than cyllin and kindred prepara- 

 tions. 



Cyllin, lysol and similar preparations have the advantages of form- 

 ing a permanent emulsion with water, they do not act on metals, they 

 are less toxic than carbolic acid and are sixteen times stronger than 

 carbolic acid. They are compatible with soap. They should not be 

 mixed with anything markedly acid. 



Lysol and cyllin are the routine disinfectants used by the author. 



The former gives a clear solution for instruments, &c., for opera- 

 tions, the latter being used for general sanitary purposes. 



For general use one may use the following : — 



For washing drains, courtyards, &c., pot. perman., i in 250; 

 cyllin, I in 200. 



For disinfecting walls, floors, furniture and clothing, cyllin, ij oz. 

 in a three-gallon bucket, or lysol, i in 40. 



For cowshed floors, dung-heaps, privies, cesspools, dust-bins, use 

 the above but double strength. 



For solid and liquid excreta use as above or chloride of lime, 4 per 

 cent. 



For oxidizing organic matter in water, pot. perman. until a pink 

 colour remains. 



For douches, ] per cent, lysol. 



For hand lotions, i per cent, solution of lysol. 



For surgical instruments, i per cent, lysol. 



For Insecticides Castellani recommends : — 



For body lice, kerosene, vaseline, guaiacol, anise preparations, iodo- 

 form, lysol, cyllin, carbol solution, naphthaline, camphor in the order 

 mentioned for efficiency. Sulphur, corrosive sublimate and zinc sul- 

 phate are useless. 



For bed bugs, kerosene, guaiacol and pyrethrum. 



For moths, naphthalene, menthol powder. The latter is repellent 

 to lice, fleas and mosquitoes. 



For patients entering the hospital with lice, &c. : strip off all clothes. 



