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I have proved, generally non-detectable in the fresh blood; secondly, the " pocket"
instrument used by Dr. Evans, although excellent for magnification and definition, is
much too small in the field for exact and prompt diagnosis ; thus, in Rangoon, it several
times gave negative results when my larger instrument readily showed the parasites
present. Dr. Evans made some post-mortem examinations at Tonghoo, which, as we
shall see directly, have a most important bearing on the relations of gastric ulceration
to relapsing fever.*
2. To Veterinary Surgeon (First-class)Frost belongs the credit of drawing attention
to the state of the stomach, ulcers in which organ are very marked in a large propor-
tion of the cases. This is a lesion generally associated with the action of an irritant
poison, and, apart from such influence, is rarely seen in veterinary practice as may be
inferred from the record of a case in vol. XIII, Veterinary Journal, page 201, where
it is noticed editorially as quite an exceptional condition. Under these circumstances
it was natural that the cause of irritation be sought for in the food and surroundings
of the animal. Firstly, the question of malicious poisoning has to be dealt with. It
seems, from the evidence bearing on this matter, that there has been at times some
dissatisfaction among the transport drivers, and it was thought that this could be
directly associated with the prevalence of the disease in different lines at Rangoon at
different times; the influence of attendants on the development of the disease was
thus far perceptible that some drivers have lost fewer of their mules than others, or
even none of those under their charge. In one or two cases the driver, after losing
all his three mules, deserted. Chemical analysis of the viscera was resorted to, but no
poison detected ; the gastric contents administered to a mule from two fatal cases
failed to communicate the disease, but the cases might have been chronic in which
all poison had passed off from the system in the earlier stages of attack, so it was
necessary to get other evidence. The disease practically occurred only among
Government animals, and it was difficult to see how poisoning the animals could
benefit any one—contractor, drivers, chumars (the carcases being burnt generally, and,
even if they were not, the skins of little value intrinsically and generally much
bruised and spoiled in this disease), or others. Again, the drivers in general seem fond
of their animals, and it is not infrequent for favorite mules to die, such as one ridden
by the Native Infantry Jemadar at Tonghoo. Further, we are acquainted with no
poisons such as would produce the lesions of the disease. Still it seemed possible, but
not likely, that some poisonous herb known only to natives had been used maliciously.
However, the clinical features of the disease were not those of poisoning, especially
was this evident when the fever was proved to be a relapsing one ; also I asked
myself, why, if due to poison, should it occur mainly at certain seasons of the year ?
So I found that the balance of evidence absolutely excluded the possibility of malicious
poisoning. We have seen how an irritant was sought for in the water used for
drinking purposes and supposed to be traced to a particular tank, which was forbidden
for use. On the same supposition the Somersetshire mules were moved for watering
from the Cemetery tank in about March 1884 to wells, in about two months after that
to the Royal Lakes, and in October 1884 to the wells again, and yet, while obtaining
well water, tank water of excellent quality from the Royal Lakes, of inferior quality
from the cemetery tank, these mules have succumbed to the disease ; moreover, of two
troops watered from the lower well (C and D), one has lost a large number of mules and
the other very few, and those fairly attributable to other causes. Thus, since of two
bodies of mules watered from the same source constantly, a large proportion of the one
died and the other practically escaped, it is evident here that the cause lies somewhere
else than in water from a special source. The experiment suggested by Inspecting
Veterinary Surgeon Shaw unfortunately was not thoroughly carried out; the eleven
experimental mules were watered from the suspected tank for eight months—April
to November 1884—but of them, some were used for other purposes; thus four of them
were exposed on anthrax graves, being allowed to shift for themselves in the matter of
food and water ; of them, two completely resisted disease and two died, their stomachs
being found ulcerated on post-mortem examination ; but whether or not they suffered
* It is right to state that Dr. Evans assures me he took sufficient time and care to examine the bood of the mules at
Tonghoo, and he is quite certain that they were all free from the parasite then, excepting one, though more or less ulcera-
tion of the stomach was found in eleven out of thirteen.