12 
THOUGHTS ON HYDROTHORAX. 
debilitating effects are soon induced; like as if it held the 
sources of life in its death-grip, for unquestionably there is 
a subtle and, when undisturbed, a latent substance or element 
pervading all material bodies, which is capable of exciting or 
destroying life. Some property of electricity in a state of 
equilibrium it may be, enshrouding and fostering a dormant 
condition, a condition at variance with the laws necessary 
for the maintenance of health ; and, if existing in this state 
up to a certain point, its inherent properties or forces so 
accumulate, that any accidental circumstance in the animal 
economy may disturb and set them in agitation, causing their 
affinities to repel or attract each other, thus setting free a 
certain amount of electric fluid, for aught we know. This 
view I respectfully, but firmly submit, may result in like 
electrical phenomena in the cavity of the chest, and it may 
be in the fluids generally. We know that the air, when it is 
surcharged with electricity, has its invisible vapour instanta¬ 
neously converted or condensed into drops of water, so 
moisture is eliminated and deposited, like dew upon the 
membranes, when the svstem is in a state of health, analogous 
to dew upon the earth ; and effusion may therefore be likened 
to, and perhaps be dependent upon the same phenomena as 
showers. I say, then, it is probable that a certain combina¬ 
tion of conditions, arriving at a certain state, result irresistibly 
in effusion; and that the substance or element is capable 
of existing in opposite states, and undergoing transmutation, 
is clearly exemplified in the laboratories of Nature and Art. 
It is very likely only a natural phenomenon, and one in 
accordance with inevitable laws, which most certainly will 
one day be clearly defined and understood. 
Auscultation and Percussion . 
The marked difference between the character of the sound 
to be heard when you apply your ear to the sides of a 
healthy horse which has been violently exercised, and one 
labouring under active disease of the respiratory organs in 
its early stage, is not so great as we should expect. It is 
true the sound of the former is somewhat more sonorous 
and distinct, and if you tap the sides with your knuckles, it 
sounds more hollow. In the latter it assumes a dull, thodden 
sound, but if effusion has actually taken place, on the side 
where it really exists, and the cavity is full, there is an entire 
absence of any sound whatever; there is a depth of water 
occupying the space between the ribs and the lungs, or else 
you have placed your ear opposite an adhesion, or again, if 
