PRESIDENCY VACCINE DEPARTMENT.            7

a very early period after the virus is removed from the arm it becomes
inert. Under the microscope the lymph is found to have undergone
transformation, and frequently very beautiful crystalizations are met
with. Destructive changes of a putrefactive nature are very generally
observable in such lymph.

The virus sent from England, as well as that procured from the
Hills, is also liable to become inert. That introduced into tubes in
Calcutta, is much more apt, however, to decompose than either of the
other varieties.

I attribute the extreme liability to decomposition to two causes :
1st, to the use of improper tubes. 2nd, to the existence in the atmos-
phere of Calcutta, in great abundance, of an active agent which leads to
rapid Putrefaction.

Measures for
obviating this
tendency to de-
compose

1st provision
of better tubes

11. In my first special report in 1865, I pointed out that the tubes
supplied by the Medical Store Department, were unlike those proposed
by Dr. Husband, which I had previously been in the habit of using.
Both the bore, and the thickness of the glass, are excessive. From
this it results, that an unnecessary amount of air is shut up in the
tubes, and an avoidable amount of heat is required to close them: both
evils of the first magnitude, when delicate results are at stake. In 1864
the imperfections of these tubes were pointed out to the Officer in
charge of the Medical Stores; and a representation on the point was
sent to the authorities who supply them in England.

I observe also, that a letter from the Government of Bengal, No.
6925, of the 2nd December, 1865, to the officiating Principal Inspector-
General, says in para. 6 : " His Honor requests that you will either pro-
vide the capillary tubes referred to by Dr. Smith, or authorize him to
obtain them at a cost not exceeding Rs. 500," as I was not in India then,
and can find no further correspondence on the subject, I do not know
what further steps were taken in the matter.

The same form of tubes is issued as before my representations
were made. The worst of the tubes are rejected, and not filled with
lymph, but when even the best are bad, such a process of selection
affords only limited advantage. Early attention to this matter is solicited.

2nd counterac-
tion of putrefac-
tive agency.

At first sight the observation that vaccine lymph, shut up in tubes
in the Delta of the Ganges, at certain seasons, has a marked tendency to,
decompose more rapidly than that similarly treated among the heights of
the Himalayah, might seem to be a fanciful one. It is in strict accord,
however, with the investigations of Schroeder and other earlier observers
on similar points, unconnected with vaccination. The numerous enquiries