19 
Cholera. 
1:1,000, no growth after 1 hour, growth in 45 minutes, liquefaction in 2 minutes 
and less. 
1:100, no growth after 5 minutes, growtn after 2 minutes, liquefaction after ^ 
minute. 
3: 100, no growth after 4 minute. 
Diphtheria. 
1:1,000, no growth after H hours, growth after 1 hour and less. 
1: 100, no growth after 15 minutes, growth after 10 minutes and less. 
3:100, no growth after 4 minute. 
Putrefying blood {50 c. c. -p 49 c. c. aq. di.st. 1 c. c. formalin). 
1 : 1 00, no growth after 1 j hours, growth after 1 hour, liquefaction after 5 minutes. 
Formalin did not work well in disinfecting instruments. Three per 
cent was efficient in disinfecting those artificially infected. 
To determine the action of formalin on larger articles pieces of cloth, 
a uniform collar, etc., were soaked in cultures of staphylococcus pyo- 
genes aureus, dried, and sprayed with formalin solutions of various 
strengths. One part was wrapped rather tightly in a towel and the 
other placed under an air-tight bell jar. After six hours the articles 
were sterile. The amounts used were 3, 5, 10, and 100 per cent, the 
results being the same. 
In the next experiment large cloths of linen were soaked in staphy- 
lococcus bouillon cultures. One was strewn with formalin powder 
which contained 20 per cent formalin and tied up fairly tight in water- 
tight tissue. After twenty-four hours some colonies grew on gelatin, 
but after forty-eight and seventy -two hours none grew; molds grew 
on all three. 
A series of experiments showed that while neither formalin 3 per 
cent or absolute alcohol alone killed anthrax spores dried' on silk 
threads, a mixture of alcohol and formalin 3 per cent killed them on 
threads moistened in sterile water after 8 minutes’ exposure. 
Also, as regards staphylococcus pyogenes aureus — 
Absolute alcohol, growth after 3 minutes, none after 4 minutes. 
50 per cent alcohol, growth after 10 minutes and less. 
3 per cent formalin, no growth in 1 minute. 
3 per cent formalin in absolute alcohol, no growth in 1 minute. 
3 per cent formalin in 50 per cent alcohol, no growth in 1 minute. 
2 per cent formalin in 50 per cent alcohol, no growth in 1 minute. 
1 per cent formalin in 50 per cent alcohol, no growth in 4 minutes, growth after 3 
minutes. 
1 per cent formalin, growth after 10 minutes. 
Walter got the following results with artificially infected stools 
(cholera and B: coli): 
1 per cent, cholera killed in 5 minutes. B. coli lived after 60 minutes and less. 
3 per cent, cholera killed. B. coli killed after 30 minutes, lived after 10 minutes. 
5 per cent, cholera killed. B. coli killed after 30 minutes, lived after 10 minutes. 
10 per cent, cholera killed. B. coli killed after 10 minutes, lived after 5 minutes. 
