476 APPENDIX 



lessened. If used in spaces containing machinery all metal parts should be coa 

 with vaseline. 



CHEMICAL SOLUTIONS 





Bichloride of mercury is usually sold in the form of antiseptic tablets. As a 

 disinfectant. for the infectious diseases it is usually used in a strength of i-iooo. 

 The solution should be made in a wooden or earthenware vessel. As bichloride forms 

 inert albuminates it should not be used in the disinfection of sputum, faeces or any 

 albuminous excreta. It must be remembered that bichloride is a mordant so that 

 any stains in soiled clothing will remain permanent. For disinfection of clothing 

 the material should be left in i-iooo bichloride for one hour. Dishes for food 

 should never be disinfected in bichloride on account of the danger from poisoning. 

 Floors and walls may be disinfected with i-iooo bichloride applied with a mop. 

 Allow the solution to dry on the floor or walls. 



Formalin. A 5% solution of commercial formalin in water (50 c.c. formalin 

 950 c.c. water) makes a satisfactory disinfectant for soiled clothing. It is also 

 valuable for albuminous material. The disinfectant must act in a strength of 5% 

 so that if i pint of fasces is to be disinfected we should add i pint of a 10% formalin 

 solution and allow it to act for one hour. 



Carbolic Acid. It is soluble in water to the extent of about 5% and in such 

 strength it is an efficient disinfectant. The solution should be made with hot water. 



In standardizing disinfectants carbolic acid is used as the standard. It how- 

 ever is expensive and there is often difficulty in making up satisfactory solutions. 

 More efficient and more convenient is the Liquor cresolis comp. U. S. P. This may 

 be prepared by mxing up equal parts of cresol and soft soap as noted on page 13. 

 This has a value according to tests made in the Hygienic Laboratory of 3, making 

 it in tests without organic matter three times as efficient as carbolic acid. Under 

 similar conditions lysol had a value of 2.12, creolin 3.25 and trikresol of 2.62. 



Equal parts of a 5% solution of Liq. Cresol. Comp. and the fasces, urine or 

 sputum to be disinfected is satisfactory for disinfection provided the mixture is 

 allowed to stand for one hour. Here we would have the effect of a 2^% solution. 

 Liq. Cresol. Comp. (5%) is an excellent disinfectant for contaminated bedclothing, 

 etc. It is also most suitable for the disinfection of floors and walls. 



Sulphate of Copper. This salt has a remarkable effect on certain species of algae 

 so that in strengths of i to 1,000,000 it is destructive. In i to 400,000 it will kill 

 typhoid bacilli in twenty-four hours in water that is not too full of organic matter. 



Hydrogen Dioxide. A 2% solution will kill anthrax spores in three hours. It 

 is useful in treatment of anaerobic infections, as gas bacillus ones. 



Chinosol. This is a derivative of quinoline, a coal-tar product. It is a yellow 

 powder readily soluble. It does not coagulate albumin and leaves no stain on 

 clothing. It is efficient in a strength of i to 500 or i to 1000. 



Lime. It must be remembered that air-slaked lime is inert as a disinfectant. 

 For disinfecting faeces freshly prepared milk of lime is excellent. It is made by 

 mixing unslaked lime with four times its volume of water. An equal quantity 

 should be added to the faeces to be disinfected. 



Chlorinated Lime. This can be purchased in air-tight containers and when the 

 package is opened it should give off a powerful oder of chlorine. 





