( ) 
ready to figlit disease in any part of the woikl. 
If ilie runicur is true iliat the anny school is to 
be soon moved to London, I am sure you will all 
join me in wishing it a brilliant future. 
lu the history of the past year theieisno great 
discovery to be recorded ; it may be looked baik 
upon as one of steady pro<:ress in elucidating some 
of the many problems of tropical medicine, the 
greatest and most beneficient being in the scientilic 
preveolion of disease. In the caseof yellow fever 
the mosquito— a Culex, not Anopheles — has been 
tried and found guilty of being the sole ageirt in 
the spread of that disease. In Havana yellow 
fever was endemic for a centuiy and a-half ; 
during the pasc year it has been freed from the 
scourge by killing Uie mosquitos in the neighbour- 
hood of each focus of disease as discovered, and 
by carefully disinfecting every house that had 
lodged a yellow fever patient in order to destroy 
the mosquitos that had bitten a sick person. This 
great sanitary triumph must ever redound to the 
honour ot American medicine. 
lN|o excuse is necessary in this Section for dwell- 
ing a little on the important subject of the pro- 
phylaxis of malaria. An epidemic of any kind 
is among the most costly in life and money tliat 
can befall a town or district. An epidemic of 
malaria differs from other oui^breaks of disease in 
this impoitant fact that its effects are not limited to 
the deaths it causes, but that it often leads to 
years of suffering, poverty, and depopulation. 
I have high authoricy for stating that, taking 
one year with another, malaria destroys twice as 
many people in India has cholera, small-pox, and all 
other epidemic diseases put together. Ic is a 
matter of history that the same cause almost an- 
nihilated the soldiers of the Walcheren exjiedition, 
and the army under Wellingt;on in Spain was so 
assailed by malaria that according to Ferguson 
the enemy and all Europe be'ieved ihe British 
forces were exterminated. Malaria stopped the 
great Panama scheme of de Lesseps. 1 have known 
districtsin Ceylonalmostdepopulated. Amostdisas- 
trous outbreak occurred some years ago at Galle a 
town previously malaria hee — attended with 
great loss of life in consequence of the construc- 
tion of a railway the embankments of which 
were made by excavating pits at the sides that 
soon were filled with lain water. In those days 
the origin of the fever was, of course, attributed 
to disturbance of soil. We now know the pits 
provided breeding places for the A aopJteks, and 
the Sinhalese and Tamil labourers from malaria 
districts supplied the organisms. 
Although we were ignorant of the true condi- 
tions which caused the outbreak, we advised 
the filling up of the pits ou the disturbance of 
soil theory with satisfactory results, proving that 
much can be done in the prevention of disease 
before full knowledge of causation is reached. 
I will only occupy a few minutes of your time 
while 1 describe two ex|ierinients — one made by 
tlie Colonial Olfice on Dr Manson's advice, and 
the other by the Japanese Governnrent, which 
cleaily show it is both possible and practicable 
to prevent malarial infection. 
I:i the experiment conducted by Drs. Sambon 
and Low in the Roman Campagna and in 
London in order to prove the iruih or error 
of the mosquito malarial theory, and also how 
far protection against malaria might be con- 
sistent with the ordinary avocations of life, two 
e.vperimeuts were necessary, one that healthy 
persons in J,4oadott sUould be bitten by infected 
mosquitos from a malarious region, and the 
second that men should live in an undoubtedly 
malarious place during Ihe fever season, bein? 
protected only fiom the biles of mosquitos. 
Those bitten in London contracted ague. Drs. 
Sambon and Low and two others lived in a 
mosquito proof hut in a most intensely malarious 
place in Italy, where all the inhabitants sullVred 
from malaria. Ibe four inhabitants of the hut 
remained perfectly healthy all the time, and, I 
believe, are so still. 
The experiments by the Japanese Government 
were carried out on the Island of Formosa, 
and they furnish a most conclusive demonstration 
of the relations between mosquitos and malaria. 
A battalion of soldiers who were completely 
piotected from mosquiti s for 161 days daring 
the malaria season escaped the disease entirely ; 
whereas there were 259 cases of malaria in 
another battalion in the came place and during 
the same length of time not protected from 
mosquitos, 
I am sure you will agree with the conclusions 
of Drs Sambon and Low that their experiments 
prove that mosquitos only are capable of trans- 
mitting malarial fever ; that protection from 
their bite implies absolute immunity ; and that 
protection can be easily obtained. If further 
proof is considered necessary for large bodies of 
men, it is furnished by the Japanese ex- 
periment. 
By a study of the life-history and surroundings 
of the Anopheles, and by varied and long- 
continued experiment, Koss has determined the 
best means of preventing malarial infection. He 
advised the extermination ol the Anopheles, a,nd 
although this is difficult it is not so difficult as 
at first sight it appears. These mosquitos breed 
in small pools of a certain kind easily recognized 
and easily dealt with, a'ways close to human 
habitations, as the females must past freqirently 
between the pools where they lay their eggs and 
the houses where they obtain their food. If the 
Anopheles are found in a house the breeding 
jiuridles are close by. The great practical points 
derived from Koss's work are two : 
1. That the life of the Anopheles is in direct 
and intimate relation with the annual epidemics 
of malaria fever. 
2. That it is only necessary to drain the 
Anoplieh's puddles and not the whole of a mala- 
rious district. 
I believe the discovery of the malaiial parasite, 
and the investigations into the life-history ol the 
mosquito which conveys it to man have placed 
us in the position to suggest measures whi^h if 
carried out would have the effect in an unhealthy 
district of largely reducing the amount of malarial 
fever and eventually of exteririinatiog it. 
1. Malarial fevers should be ine'uded and noti- 
fied among infectious di-?eases, so that precautions 
could be taken to prevent thair spread. 
2. Persons, especially children, suffering from 
malaria, primaiy infections or recnrrents, should 
be isolated and treated with quinine to prevent 
as lar as possible the infection of mosquitos. 
.S. Persons infected with malaria should be 
prevented coming to a healthy place to infect 
mosquitos. 
4, The pudilles in which the Anopheles breed 
.should be drained and lilted up or treated with 
kerosene to destroy tUe larvaei 
