I)H. S. H. LONG ON TIIE MOSQUITO-MALARIA THEORY. 189 
that which is the subject of ray present paper. It has of late not 
only been engaging the closest attention of members of my own 
profession, but it has also excited considerable interest in the minds 
of the general public. And rightly so ; for when we consider the 
far reaching, and it would seem ever-increasing, extent of the British 
Empire, and the fact that her sons may be called upon at any time 
to uphold its dignity and freedom of action in any part of the world, 
it is only right that they should possess a full knowledge of all 
available means of avoiding one of those diseases which is so uni- 
versally present within certain latitudes, and which is the cause of 
so many shattered constitutions amongst our soldiers in after life. 
In the elucidation of this Mosquito-Malaria Theory, which, by 
the way, was first promulgated by one of our own epidemiologists, 
Dr. Patrick Manson, I am proud to say that Englishmen may be 
accredited with their full share of the discovery, which has only 
been arrived at by a most careful and scientific investigation. 
Now Malaria or Ague, for the two words are synonymous, is 
a disease of varying type, but it may roughly bo said to be charac- 
terised by regularly or irregularly intermittent fever. There are 
usually three stages : the cold shivering stage, when the temperature 
of the body is rising ; the hot stage, when the temperature has 
reached its height; and the sweating stage, when the temperature 
is falling again. These three stages constitute an “ attack,” and as 
to whether these “attacks” occur every day, or every other day, or 
with two days interval, the Ague is said to bo quotidian, tertian, or 
quartan in typo. Such attacks may recur, unless checked by the 
internal administration of some drug, with more or less regularity 
for an indefinite period ; but what is perhaps most aggravating 
about the disease is the fact that the sufferer may have been free 
from “ fever ” for a long period of time — months or even years — 
and yet after this interval he may get another attack for no apparent 
reason. Such is the common experience of Anglo-Indians who 
return to reside in this country. 
Malaria has been recognised as a definite disease since the time 
of Hippocrates; and, moreover, the older observers were fully alive 
to the fact that it was most prevalent within certain latitudes. They 
further associated the disease with unhealthy and swampy places, 
where the air was continually being poisoned with the miasma 
arising from the soil. The disease was known to be infectious, and 
