10 
THE TROPICAL AGRICULTURIST [July a, 1894. 
is from the chief ingredient being sodium per- 
manganate, .and of the latter from the chief 
ingredient being sodium nianganate. Their value 
depends on the amount of available oxygen 
present. According to A. H. Allen's analyses, 
(Year Book of Pharmacy 1871) the green fluid con- 
tains 3"883, and the crimson fluid 3 921 grams of 
available oxygen per litre. 
Hartman's crimson salt is a mixture of sub- 
stances, each of which possesses antiseptic pro- 
perties. The compound as patented consists of 
potassium permanganate, 1 part ; potash alum, 
8 parts ; borax, 1 part ; common salt, 6 parts. 
Phenols, 
Most of the substances containing phenyl 
C e H 5 have antiseptic properties. The best 
known of these bodies is carbolic acid C^H^OH, 
the synonyms for which are phenol, phenyl 
hydrate, phenyl alcohol, phenic acid, coal tar 
creosote. The best quality consists of almost 
chemically pure phenol ; other qualities contain 
considerable quantities of homologous bodies, such 
as cresol, also called cresylic phenol, cvesylic acid, 
and cresyl alcohol C c H 4 OH,CH 3 . Calvert's No. 5 
carbolic acid is mainly composed of cresylic acid. 
Cresylic acid is considered little inferior to true 
carbolic acid as a disinfectant ; but it is different 
with the neutral tar oils which sometimes con- 
stitute as much as 50 per cent of the carbolic acid 
sold to Municipalities and Boards of Health. 
Carbolic acid containing tar oils should be rejected, 
as the latter have almost no antiseptic value. 
Mixtures of carbolic acid and slaked lime are 
sold as disinfecting powders. They contain from 
about 1 to 18 per cent of carbolic acid. Carbolic 
acid is considered to be much less active in this 
form, and, when cresylic acid is substituted for 
carbolic, the powder according to Dr. Tidy is 
practically valueless. The source of ordinary car- 
bolic acid is gas tar. Phenoloid bodies of consider- 
able antiseptic value arc now prepared from 
blast furnace creosote oil, which is much richer 
in phenoloid bodies soluble in caustic soda, than 
the corresponding coal tar creosote oil, the 
proportion in the former being from 23 to 35 per 
cent, as against 5 to 10 per cent in the hitter. 
The phenoloids from blast furnace creosote oil, 
when partially purified, furnish the " neosote'' 
of commerce, which is considered equal in anti- 
septic value to crude carbolic acid, although it 
contains only from 1 to 2 per cent of crystallisable 
carbolic acid. It contains, however, a large pro- 
portion of cressols, and some of the higher 
homologates. 
Other substances besides lime have been 
used for the absorption of carbolic acid in the 
manufacture of disinfecting powders. McDougall's 
disinfecting powder is a mixture of carbolic 
acid and crude sulphite of calcium ; Calvert's 
carbolic powder has for the absorbent of the 
carbolic acid the siliceous residue left from 
the manufacture of aluminous substances from 
China clay. Calcium sulphate, kieselguhr (the 
spongy siliceous mineral used in the manufacture 
of dynamite) peat, ground blast furnace slag, 
limestone, gas lime, and dried borax have all 
been used in the manufacture of carbolic powders. 
Dr. Crace Calvert, whose name is more 
particularly identified with the carbolic acid 
industry, made several series of experiments with 
a view to compare the antiseptic power of carbolic 
acid with other substances. Dr. J. Dougall 
also made a number of interesting experiments. 
I shall quote here in tabular form Calvert's series, 
in which he experimented with 1 part of antisep- 
ic substances in 1,000 parts of a solution of 
albumen. The figures given repreKent the 
number of days before vibrio life (animalcules), 
putrid odour, fungi, and mouldy odour were 
respectively developed. 
Results of Ggfoerfs Experiment* with inthmUm. 
Substance Used. 
si i. 
5 -. 
% r 
— - 
So 
Acids : 
Sulphurous 
11 
over 40 
Nitric 
10 
50 
Sulphuric 
9 
Carbolic 
over 40 over 40 
Cresylic 
over 40 
over 40 
Acetic... 
30 
Picric 
17 
over 40 
Alkalis : 
Lime... 
13 
19 
Potash 
16 
Soda ... 
23 
31 
Ammonia 
24 
50 
Chlorine Gas 
7 
21 
Chlorinated Lime 
7 
18 
Chloride of Zinc 
over 40 
over 40 
Chloride of Aluminum 
10 
over 40 
Bisulphite of Calcium. 
11 
21 
Sulphate of Iron 
7 
over 40 
Permanganate of Po- 
tassium... 
9 
50 
Turpentine Oil 
14 
over40 
1 
•it 
10 
9 
over40 
over 40 
9 
19 
jver40 
18 
20 o 
21 
16 
50 
21 
N 
15 
22 
42 
= i 
0°, 
over 40 
23 
11 
over 40 
over 40 
50 
over40 
over 40 
29 
ver40 
over 40 
50 
over 40 
over 411 
over 40 
It will be observed that turpentine oil possesses 
considerable antiseptic power. This property of 
oil of turpentine has been utilized in the dMn 
fectant known as "Sanitas," which is prepared by 
blowing air through warm oil of turpentine in 
presence of water. This treatment produces cam- 
phoric acid and other oxidation products, as well 
as the substance hydrogen peroxide, which itself 
is a powerful antiseptic owing to its proi»erty of 
giving off oxygen in a very active state. C T 
kingzett is the inventor of Sanitas. Besides oil 
of turpentine other essential oils, such as Eu 
calyptus and Cinnamon oils, also oil of pepper- 
mint, possess strong disinfecting properties. 
A comparatively new disinfectant, a product 
of tar oil, was introduced into Ceylon in 18 c l 
&n Dr - Jfr*** th , e , Principal Civil Medical 
Officer. It is named lysol, and it is said to 
be possessed of remarkable properties which 
make it specially valuable for disinfecting 
surgical instruments. I extract the faUowinl 
from an article by Dr. VaL Gerlacfa in Zeitg. 
chrift fur Hygiene edited by Dr. R. Koch and 
Dr. C. Flugger, vol 10, part 2, 1891 
Dr. Gerlach says :— " It is a most valuable dis- 
infectant, and in the destruction of bacteria 
is more effectual than carbolic acid and creo 
lm.* It is valuable for disinfecting the hands 
This can be effected with one per cent sola' 
tion of lysol without soap. For the disinfec 
tion of sick rooms, sputa, and excreta it is 
more efficacious than any other disinfectant 
By spraying walls with a three per cent solu- 
tion of lysol they will be effectually disinfected 
In comparison with such other disinfectant* a* 
carbolic acid, creolm, and corrosive sublimate 
which closely approach it in efficacy lysol is 
Ivy far the least poisonous." 
The following are the chief antiseptics that 
have been used as food p reservatives :— Sul- 
* A product of tar oil. 
