55G 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[January 11, 1873. 
sider the germ theory of disease generally. It has been 
conclusively proved that all rooms are tilled with a cer¬ 
tain amount ot dust moving about in variable quantities 
—at least, to all intents and purposes, it may be con¬ 
sidered as never being absent. The greater proportion 
of this dust, as shown by Tyndall in the analysing tube, 
is organic, or, in other words, can be destroyed by heat. 
Some medical men of great celebrity are of opinion that 
most of the epidemic diseases are carried through the 
atmosphere in the form of germs peculiar to each dis¬ 
ease—that certain diseases again may be instigated by 
the change or fermentation induced during the growth 
of germs (not peculiar to the disease), at the expense of 
their surroundings. As regards experiments performed 
upon the development of bacteria, they would properly 
only bear upon epidemic diseases from this point of 
view, but I myscll do not see that there is anything 
particularly to connect them with small-pox or such like 
contagious diseases. They are always the forerunners 
of putrefactive change where atmospheric air has been 
in contact, but this simply proves that the germs of 
bacteria are always present in ordinary atmospheric air. 
Here is a substance that was once a solution of milk- 
sugar, now converted into solid lactate of lime by germs 
taken at as high an altitude as the top of Nelson’s 
Pillar. Lut these results can be obtained equally well 
when there is no small-pox in the city. As regards the 
nature and actual appearance of most contagious germs 
connected with epidemics, I plead total ignorance, and 
think the biologist, physicist and chemist are all equally 
ignorant. We are not yet armed with instruments 
powerful enough to investigate or classify the “ milky 
way of minute organism, as Ehrenberg terms it. 
There is, however, another view to take of the at¬ 
mospheric propagation of disease, which, I think, has 
been too much lost sight of. This is the mechanical 
action of this dust, or the raft theory, as I will call it. I, 
however, lay no claim to the use of the word raft. It was 
used by Professor Tyndall in one of his lectures to ex¬ 
plain how the particles of a non-volatile salt, chloride of 
sodium, were always found in the air. Now, as we know 
that the virus of small-pox may be dried without im¬ 
pairing its activity, we have all the requisites for dis¬ 
semination by the atmospheric rafts. It is self-evident 
that we can inoculate contagious diseases directly or in¬ 
directly (I use the word contagious and other similar 
words in their strict sense). The Otomak anoints his 
thumb nail with the deadly curara, and scratches his 
enemy, but the Indian generally anoints his arrows with 
it to send his poison through the air, and yet these 
arrows are equally efficacious as engines of death. Is 
not this the raft theory of indirect contagion merely ex- 
aggerated ? If we consider the immense amount of 
inoculable matter that is disseminated in a city like this, 
where 600 to 700 lie ill of the same contagious disease, 
we shall see no difficulty in arriving at this conclusion. 
I have no hesitation in saying that there is not a cubic 
inch of atmosphere in Dublin where the small-pox virus 
is not. But, like all poisons, there is, I suppose, a point 
of attenuation where it is inert, and to keep it below that 
point is the great use of volatile disinfectants. The dried 
virus floating upon those rafts cannot be affected by 
non-volatile disinfectants. 
I listened a few nights ago with a great deal of plea¬ 
sure to a paper read by Dr. Cameron upon this subject, 
it being filled with a number of observations of great 
originality. The tendency, however, as I understood it, 
was rather to undervalue disinfection as regards epi¬ 
demics of this class. Now, I am of opinion that it 
would be dangerous in the extreme to cast away these 
now old and well recognized friends. In fact, to me it 
seems to be only within the last few years that we have 
been beginning to understand the principles of disinfec¬ 
tion. We are frequently told by the medical men that 
there is nothing like “ fresh air,” which, translated che¬ 
mically, means oxygen, plenty of it, and in an active 
state. Such remarks are the true harmonic chords of 
science , but how are we to get fresh air in a contami¬ 
nated city, if my mechanical theory of atmospheric dust 
is correct, or has the slightest stability whatever ? Does 
not the real difficulty of disinfection lie in our misappli¬ 
cation of each particular disinfectant which has its pe¬ 
culiar function, and our want of knowledge of its action 
on those germs at present unknown ? If we use chlori¬ 
nated lime to disinfect a room (chlorinated lime being 
simply an oxidizer), what do we do but facilitate the 
efforts of the atmospheric oxygen to purify by oxidation ? 
We charge the air with nascent oxygen, or that element in 
its most active form. Thus this air that had been already 
artificially deprived of its activity outside by contact 
with contagious matter, is re-oxidized to its maximum 
capacity. _ Now, although this is quite consonant with 
our chemical knowledge, it might be said that, after all, 
it is but a theory ; but let us see how it agrees with our 
experience. 
On the first week in November, 1871, in an establish¬ 
ment, the name of which, from obvious reasons, it is not 
desirable to mention, a case of small-pox occurred. As 
there were about 200 beds upon this establishment, 
it is almost needless to remark that considerable 
alarm was felt by those with whom rested the responsi¬ 
bility of management. A consultation was held, and a 
well-known and well-advertised disinfectant was used 
with every precaution as regards cleanliness. Imagine 
the consternation when case after case was sent out of 
the house, until the eleventh was taken to the hospital 
on the 6th January, who died on the 11th of the same 
month—a case every fifth day. A consultation was 
again held, and with advice the following plan was 
adopted. The disinfectant was changed, and the use of 
carbolic acid and chlorinated lime was agreed upon. 
The carbolic acid (pure) was chiefly used in water-jugs, 
a few drops in each jug. A man was told off specially 
to disinfect the place, and to do nothing else. In the 
morning he made his solution of “chloride of lime,”’ 
about ^ lb. or 1 lb. to the gallon of water, in a large tub. 
It was allowed to subside, so that it was quite bright and 
clear when he wanted it for use. At three o’clock p.m., 
he went through all the rooms, sprinkling the solution 
over every floor, and the windows were left open, so 
that the rooms were dry by the time they were required 
for use, equal attention being paid to the mechanical 
cleaning of the walls. The change in the system of 
disinfection was made on the morning of the 11th of 
January, the day when the last case was buried, and 
from that day to the present there has not been a single 
case of small-pox in this seething* mass of humanity.*' 
Can we believe, after such an instance as the above, that 
there is nothing in disinfection if systematically and 
judiciously applied ? I may mention that other establish¬ 
ments in Dublin have had a very similar experience. 
Cresylic and carbolic acid are the most efficacious volatile 
antiseptics, and chlorinated lime one of the most effica¬ 
cious as an atmospheric oxidizer. Permanganate of 
potash is invaluable for certain special applications. 
Here is a simple experiment which, I think, conclusively 
proves the value of chloride of lime as an oxidizer. I 
blow through a series of wash bottles and tubes. In 
the first bottle the air traverses a fermenting mass con¬ 
taining a weak solution of a ferrous salt. If the air 
contained any readily available oxygen (it matters not 
whether we consider it ozone, or condensed oxygen, or 
nascent oxygen, if it does its work), it will be deprived 
of it. This fact is demonstrated by being passed over- 
ozone test-paper contained in the next tube. There is 
no evidence of decomposition, it is then passed in the 
next bottle through water containing a few drops of 
chlorinated lime, and then through a wash-bottle con- 
On the 24fch of June, when this paper was going through, 
the press, this house was still free from any case of small¬ 
pox. 
