50 
EPIDEMIOLOGICAL SOCIETY. 
the formation of this Society have been so fully stated, that it 
would be superfluous to say thing more on this head. 
Physiology has made prodigious strides of late years. I 
need only recal to your minds Professor Schwann’s theory of 
cell formation, whereby he has established, by observation with 
the microscope, the proposition, that there is one common prin- 
ciple of development for the elementary particles of all organized 
bodies. This discovery, so brilliant as to have won for its author 
the Royal Society’s Copley Medal for 1845, and which must 
be ranked amongst the most important steps by which the 
science of physiology has ever been advanced, evinces how the 
improvement of a scientific instrument leads to the improvement 
of science itself, and encourages a hope that our investigations 
may be enriched by this powerful means of interrogating Nature 
with regard to her most minute and secret operations. From 
meteorology, pursued, as it now is, under the guidance of a 
master mind, by a society expressly devoted to that branch of 
science, we have grounds for expecting many valuable facts 
applicable to the elucidation of our subject; and 1 trust that one 
of our earliest acts may be an endeavour to form a close con- 
nexion with that Society. 
The progrees of medical science itself has been no less con- 
spicuous of late years than that of many branches of natural 
knowledge. The great discoveries of Laennec have created a 
new era in medicine, and have given an importance to physical 
diagnosis, the influence of which has extended far beyond the 
limits of those diseases which he made the particular objects of 
his study. Statistics, too, have supplied us with a new and 
powerful means of testing medical truth, and we learn from the 
labours of the accurate Louis how appropriately they may be 
brought to bear upon the subject of epidemic diseases; his re- 
port, when engaged on a French commission for investigating 
the yellow fever at Gibraltar, in 1828, being a striking instance 
of their successful application. 
As a matter for scientific inquiry, the subject of epidemics 
seems peculiarly well suited to occupy the attention of a society. 
Diseases which affect only individuals here and there admit of 
investigation by single observers, and perhaps are thus best 
studied ; but those which affect masses of mankind, and whose 
ravages are spread over a wide extent of the earth’s surface, 
require the combined effects of numerous labourers, and the 
various researches of minds directed to different branches of the 
inquiry, and contemplating the phenomena from different points 
of view. They require that observations should be simultane- 
ously carried on in many and widely-distant places, in order 
