188 DR. S. H. LONG ON THE MOSQUITO-MALARIA THEORY. 
XI. 
THE MOSQUITO-MALARIA THEORY. 
By Sydney II. Long, M.B. 
Read 26th February, 1001. 
The subject of my communication this evening, viz., the relation- 
ship between the Mosquito and the disease known as Malaria, is 
one which at first sight might appear to be of too technical a nature 
to be discussed by the members of this Society ; yet it is really one 
upon which many of our members can probably add some new facts 
to those that have so rapidly been brought to light by investigation 
in this country and elsewhere during the last year or so. For this 
reason I have thought it fitting to attempt to lay before you in 
review a brief resume of the work in this connection that has 
already been accomplished, and with which some of you are probably 
in part familiar. 
Two or three hundred years ago the causes of many diseases were 
represented as Spirits, Witchcraft, the Evil Eye, &c., only to be met 
by such means as the King’s Touch, Spells, and Incantations ; and 
even at the present day, in some of the outlying parts of this county, 
we find that traditional superstitions of this nature still have their 
advocates amongst some of the less enlightened of the rural popula- 
tion. Happily, however, for human nature, the Nineteenth Century 
produced men who would not rest content with doctrines based 
upon such slender foundations as those they inherited, and with 
the increasing means of research that have gradually been evolved 
out of the microscope and in other ways, the study of medicine may 
now justly be called a true science. 
One of the greatest, and most far-reaching in its beneficial effects, 
of the discoveries of the Nineteenth Century is, in my opinion, 
