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THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. [September 30,1871. 
DISINFECTION. * 
No. I. 
A disinfectant is, in the broadest acceptation of the 
term, anything which counteracts infectious, contagious 
or effete matter. How a few disinfectants produce their 
♦effects is perfectly understood, and presents no kind of 
mystery ; how other disinfectants work is matter of dis¬ 
pute, and regarding the action of a good number of them 
we have as yet hardly arrived at the stage of controversy. 
The material whose effects are to be opposed by disin¬ 
fectants is held by some authorities to be animal or vege¬ 
table germs, and by others to be subtle organic poisons 
of surpassing power; and possibly enough may be of all 
these kinde, but must at any rate consist of complex 
organic matter. In common with all organic matter, 
the matter of contagion may be destroyed, and therefore 
Tendered inoperative, by exposure to a red heat, in pre¬ 
sence of excess of oxygen. Fire, therefore, is a disinfec¬ 
tant whose action is intelligible, and whose absolute 
♦efficacy is undoubted. It is one of the most ancient dis¬ 
infectants, and is, for many purposes, unrivalled, and 
likely to remain so. 
The action of destructive chemical agents, such as hot 
♦concentrated sulphuric, nitric or chromic acid, is, in like 
manner, quite intelligible. Disinfection by such means 
is perfectly certain, but it would be costly, and there are 
mot many instances where such agents can be employed, 
mnd where fire might not be resorted to with greater 
•economy. 
We have instanced disinfectants which are effective 
and impracticable, in order to throw light on those which 
are practicable and not effective or much in vogue at the 
present time. Chlorine, which, in the form of bleaching 
powder, is much employed as a popular disinfectant, 
will necessarily destroy contagious matter, as it does all 
organic matter if suitable precautions be taken to ensure 
the conditions under which it can act thoroughly. But 
lo use chlorine under these conditions is no more practi¬ 
cable than to use boiling concentrated nitric acid, and 
the manner in which chlorine is actually used, and that 
which alone is practicable, is not effective. 
Suppose, instead of burning the clothes of the plague- 
stricken patient, we were to reduce them to pulp, bleach 
the pulp, and make paper of it, should we get plague 
paper from the plague rags ? We cannot guarantee that 
we should not, but if we pushed the action of the chlo¬ 
rine further, destroying the pulp so that it could not 
make paper, and until complete chemical disintegration, 
then we could guarantee that it would not be infectious. 
T*f, then, there be doubt whether the paper made from 
some descriptions of infected rags be infectious, what 
shall we say of the chances of the decomposition of in¬ 
fectious matter by the popular expedient of just sprink¬ 
ling clothes with a little bleaching liquor ? Fumigations 
of sick-rooms with chlorine gas are not likely to be 
•effective, for long before the proportion of chlorine in the 
atmosphere could reach the point at which we could hope 
for any attack of infectious matter existing in the atmo¬ 
sphere (and certainly very long before we could guarantee 
any attack of the infectious matter), the smell of chlorine 
would have become unendurable. In fine, the actual 
practical employment of chlorine, as a disinfectant, does 
not rest on a sound chemical basis, and we are not war¬ 
ranted in assuming that any great good is done by it. 
Leaving disinfectants which aim at the chemical dis¬ 
integration of infectious matter, we pass on to others, 
the modus operandi of which is in dispute. Corrosive 
sublimate, carbolic acid and sulphurous acid,—do they 
poison the germs, or are they chemically incompatible 
in relation to the organic poisons ? We shall not discuss 
this question on the present occasion, but it is a fact, as¬ 
certained by experience, that these substances, in common 
with very many others, have some power of suspending 
the action of infectious matters, Of late years it has 
been the fashion to single out carbolic acid as pre¬ 
eminently serviceable. But Dr. Sansom, who is one of 
the warmest advocates of the use of carbolic acid, has^ 
shown that if we measure its activity by its power of 
arresting fermentation it is far behind corrosive subli¬ 
mate ; and if by its destructive action on low forms of 
animal life—on spermatozoa, infusoria and entomostraca, 
it comes behind corrosive sublimate and most of the com¬ 
monest acids. In short, there is no reason why carbolic 
acid should be so singled out, whilst its being notoriously 
poisonous makes it no fitter for general and popular use 
than corrosive sublimate. 
As we have said, the list of disinfectants is very wide. 
It includes such substances as common salt, which, ac¬ 
cording to Dr. Sansom’s table, has about one-twentieth 
the disinfective power of carbolic acid. It appears to us 
that, whilst possibly all may have their uses in skilled 
hands, for household and popular use, we must avoid 
corrosive chemicals, poisonous substances, and bad-smell¬ 
ing things, and select agents which, having none of these 
properties, can be employed thoroughly and unsparingly. 
The property of deodorizing is also one which will be 
valued in a popular disinfectant, and since most ot the 
common bad smells are stinking alkaloids, a great variety 
of substances, including all the acids, will possess this 
property. 
We shall return to the subject and discuss the uses of 
the several disinfectants. 
THE INDIA-RUBBER OF COMMERCE, 'WITH 
REMARKS ON ITS PREPARATION. 
BY JAMES COLLINS. 
American Varieties. —The Brazils supply the finest 
rubber known to commerce as ‘‘Para.” It is obtained 
from different species of Seringa —Siphoma [ZZ eved]. 
The trees are very common in the Amazon districts, and 
Para is the port of shipment,—hence the name. Sipho- 
nia elastica (or Hcvca Guayancnsis') has long been known. 
The rubber is obtained from the trees in the following 
manner:—A deep transverse cut is made through the 
bark near the base, then one perpendicular to near the 
beginning of the branches, and from this other cuts in a 
diagonal direction are made. 
The juice flows out, of the consistency and colour of 
thick cream, into a basin of clay placed at the base to 
receive it. This cream contains about 30 per cent, of 
pure rubber. Clay moulds are then dipped into the 
crude milk, to which the rubber adheres in a thin film, 
and is dried over a fire made of the oily fruits of the 
Urucuri palm. Sulphur is also used to expedite the 
operation, so that vulcanization is not so new as patents 
would lead us to believe. The same process of dipping 
and drying is repeated till a sufficient thickness is at¬ 
tained and the moulds removed. These successive coat¬ 
ings give the rubber the laminated appearance which is 
so very noticeable in most descriptions of Brazilian 
rubber. In the case of Ceara rubber, the trees are in¬ 
cised, and the rubber allowed to dry on them, and after¬ 
wards picked off, giving the rubber a stringy character. 
Para rubber is known under four forms,—1, flat pouches, 
or biscuit; 2, the well-known bottles: 3, negro head; 
and 4, “scrap.” Of these, the first is the best—the last 
two consisting of refuse. 
British and French Guiana yield but little rubber, 
although capable of yielding much larger quantities. 
It is probably obtained from the same tree as the Para 
kind, but is not equal to it in quality. 
Venezuela, New Granada, Ecuador, Peru, Costa 
Rica, Nicaragua, Salvador, Honduras, Guatemala 
and Mexico, all yield india-rubber in greater or less 
quantities, and all too obtained, there is reason to believe, 
! from one and the same tree. This tree is called by the 
* Reprinted from the Lancet, Sept. 20, 1871. 
