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from relapsing fever was not ascertained, and we have no evidence to show that the
ulceration depended on any cause other than their vagabond mode of existence. One
of the experimental mules died of " ulceration of the stomach," i.e., that lesion was
found after death; another died on 27th November 1884, and was carefully examined
by me. He showed no signs of relapsing fever and his stomach was not ulcerated. I
have carefully examined five of these mules for some time and found them anæmic,
but not suffering from relapsing fever, as I am in a position to state positively. The
remainder of these mules got fat and have been sent to the regiments for duty. Thus
three cases of " ulceration of the stomach " have followed in eleven mules experimented
on ; of these, two are excluded as having been not treated in accordance with the
conditions of the experiment, and the single remaining case may have been due to
other causes operative in the station at the time. Six animals certainly, and two
more probably, did not suffer from drinking the water of tank No. 1. Such results as
we can obtain from this imperfect experiment are, therefore, opposed to the view that
some irritant in tank No. 1 water caused the disease. The water of the tank in question
was in November 1884 bright and sparkling, but I find that in January 1885 it has
become almost green from plant growth and contains much organic suspended matter,
both animal and vegetable, and there is a scum on its surface in places, especially
at the corner near the road from the Somersetshire lines, where the tank is freely
accessible for drinking purposes. The corner near the Depôt Lines where the animals
used to be watered is comparatively pure, and there is no possibility of sewage
contamination of this tank. It contains fish and tortoises. The arguments against this
special tank are defective. My researches have brought to light error in some matters
which are advanced as facts; thus one case of the disease occurred in the European
Infantry mules in December 1883 ; again these mules seem to have been watered at
the cemetery tank, not No. 2, but, even if they were watered at the latter, it is not likely
that on all occasions they would have passed the accessible eastern corner of tank
No 1 to go a quarter of a mile farther on to tank No. 2. The supply of water to the
dep6t mules while in quarantine at Kokine is not mentioned, and it is not considered
that a transport mule waters almost anywhere, if used for puckal work at the tank
to which he goes, if on orderly duty at every place where opportunity offers, and the
same with other duties. It is practically impossible, from the very nature of the
service, to prevent mules obtaining water from various sources, and the probable face
that private animals—certainly the hired mules and ponies—have not been involved in
the outbreak seems to indicate that the drinking water may be very bad and constantly
varied without causing the disease. It is, on the other hand, difficult to prove that
an animal has not had water more or less directly associated with a suspected source ;
thus the latter may have been brought up in mussack or puckal, used afterwards for
the drinking water. I may sum up my views on the question of water contaminated
from certain sources by saying that, although not absolutely disproved, it is not
probable ; the balance of evidence is against any single collection of water being the
focus of disease and as such acting as an irritant in the generation of ulceration
of the stomach. The holders of this view of the nature of the British Burma disorder
argue, feasibly enough, that the occurrence of the disease at a special season of the
year is probably due to that being the season when low organisms in water throw
off their active reproductive elements which may be noxious to mules, but this
involves a supposition which requires to be substantiated. They further argue
that non-specific inflammations sometimes, especially in the tropics, manifest a certain
degree of periodicity. The former argument may possibly bear on the established
pathology of relapsing fever ; the latter may be dealt with by saying that wo can
explain the periodicity, which is more regular and systematic than in other diseases,
much more satisfactorily, for we find it in direct association with an organism in the
blood. Having thus completed my argument against the disease being due to the
action of an irritant locally on the stomach, i.e., ulceration of the stomach pure and
simple, I must now examine the question of the relations which ulceration of the
stomach bears to relapsing fever in this outbreak .
3. The disorder was at one time mentioned in official returns as " ulceration of
the stomach," and measures of treatment were adopted accordingly. Having been
specially detailed for the investigation of this disease, I was enabled to devote to it