BRITISH ASSOCIATION TOR ADVANCEMENT OF SCIENCE. 641 
from the hydraulic excretory system. Agriculture, let me repeat, has made, 
aud is making, great and encouraging progress, but much yet remains to be 
done. Were agriculture adequately advanced, the great problem of the 
London sewage would be speedily solved. Can it be supposed, if the rural 
districts about the metropolis were in a condition to avail themselves of a 
supply of pipe- water not more than equivalent to that which a heavy shower 
of rain throws down on 2000 acres of land, but a supply charged with thirty 
tons of nitrogenous ammoniacal principles, that such supply would not be 
forthcoming, and made capable of being distributed when called for within 
a radius of one hundred miles ? To send ships for foreign ammoniacal or 
phosphatic excreta to the coast of Peru, and to pollute by the waste of 
similar home products the noble river bisecting the metropolis, and washing 
the very walls of our Houses of Parliament, are flagrant signs of the desert 
and uncultivated field where science and practice have still to co-operate 
for the public benefit. 
Result oe the application op Scientipic Discoveries. 
By a far-seeing one, the man of science will be regarded with a favorable 
eye, not less for the unlooked-for streams of wealth that have already flowed, 
but for those that may in future arise out of the application of the abstract 
truth to the discovery of which he devotes himself. 
Who that watched the philosophic Black experimenting on the abstract 
nature of caloric could have foreseen that his discovery of latent heat would 
be the stand- point of Watt’s invention of a practically operative steam- 
engine ? How little could the observer of Oersted’s subtle arrangements 
for converting electric into magnetic force have dreamt of the application of 
such discovery to the rapid interchange of ideas now daily practised between 
individuals in distant cities, countries, and continents ? Some medical 
contemporaries of John Hunter, when they saw him, as they thought, 
wasting as much time in studying the growth of a deer’s horn as they would 
have bestowed upon the symptoms of their best patient, compassionated, it 
is said, the singularity of his pursuits. But by the insight so gained into 
the rapid enlargement of arteries, Hunter learned a property of those 
vessels which emboldened him to experiment on a man with aneurism, and 
so to introduce a new operation which has rescued from a lingering and 
painful death thousands of his fellow-creatures. Our great inductive phy- 
siologist, in his dissections and experiments on the lower animals, was 
“ taking light what may be wrought upon the body of man.” The pro- 
duction of chloroform is amongst the more subtle experimental results of 
modern Chemistry. The blessed effects of its proper exhibition in the 
diminution of the sum of human agony are indescribable. But that divine- 
like application was not present to the mind of the scientific chemist who 
discovered the ansesthetic product, any more than was the gas-lit town to 
the mind of Priestley, or the condensing engine to that of Black. 
Although in the above extracts we may have exceeded our 
usual limits, yet the difficulty has been to make selections 
where all was so beautiful, so true, and so useful. Hereafter 
we may collate some facts, appertaining to those divisions of 
science that bear upon veterinary medicine, taken from the 
reports of the different sections of the Association. 
XXXI. 
85 
