, 1876-11-04

mCntS relating 10 neat ana llElII
In 1904 he married the widow Of the
celebrated chcmcist, LavoiSicr and retire
rd to the villa of Anteuil, where he died
in 1914, aged 81,
1t is II remarkable fact that Lnvoisicr
WAS the first to establish the import
ant doctrine of the indestruCtibility OF
matter, and that Count Rumtord first
laid the foundation for the still more in,-
purtant though less obvious doctrine of
the indcstruCtbility OF force.
Having thus glanced briefly at his ca
rccr, now pass to the discovery ON
which Count Rumford's fame IN the fu-
turc will chiefly rest promising that be-
fore his time heat was supposed to he a
. material substance, and was called the
fluid matter of heat, or icaloric. In in
Producing the subject to your notice |
will quote from one of his own papers,
describing his experiments, published in
the Transactions of the Royal Society for
1898. He says; "By meditating on
the results Of all these experiments, we
are naturally brought to that great qucs
ton winch has SO often been the subject
of speculation among philosophers nnmc-
ly: What is heat? Is there such n
thing as an igneous fluid Is there any
thing that with propriety can be called
calOrc ~
We have seen that very considcra-
hle quantity OF heat may be excited by
the friction OF two metallic surfaces, and
given off in constant stream OF tluX, in
all directions, without interruption or in
termission, and without any signs OF d.
minUation or eEhduStiOn In reasoning
on this subject we must not forget that
most remarkable circumstance, that the
source Of the heat generated by friction
in these experiments appeared evidently
to be inexhaustible. 1t is hardly neces-
s0ry to add that anything which an IN.
Wlated body or system of bodies can con-
tinue to furnish UithOW HmitdtiOR, can
not possibly he material substance; and
it appears to me to be extremely difficult
if not quite impossible, to form any dis
tinct idea of any thing capable of being
excited and communicated in those ex
periments except it be MOTION"
Rumford's experiments, had their re-
suits been generally known and apprc-
ciated, would have Immediately annihi-
lated the material hypothesis Of heat ;
but the time had not yet come for such
consummation.
lie even advanced the question to its
quantitative and highest stage, pIopos-
ing to lind out how much heat II given
amount of motion would be converted
into; and reached the approximative
result that 040 pounds falling one foot
would raise one pound of water one de-
gree of heat Of the scale OF Fahrcnheit-
This value however, as lac himself no.
tice,l, must be too high, us no account
was taken OF the heat lost by radiation.
Just fifty years after the experiment of
RumGord, DIR. j. p. Joule, of Manchester,
England, and DR., J. r. Mayer, of He'll
bronn, in Germany, independently, and
by most delicate and elaborate series
of experiments, determined that 772
pounds falling one foot would beget
sufficient heat to raise one pound of
water one degree of Fahrenheit's ther-
mOmetei. This law is known as the
mechanical equiralent Of heat, and is now
adopted as an established formula in all
works of science. The experiments of
Joule and Mayer do not detract in any
way from the merit of those OF Rumtord.
The earliest numerical results in science
are rarely more than rough approxima-
tions, yet they may guide to the estab-
lishment of great principles.
Rumford's ideas on the general sub
ject of forces were far in advance of his
age. He regarded the power Of animals
as due to their food, therefore as having
definite source and not created; and
thus he applied his views of torce to the
organic world.
Having now introduced Benjamin
Thompson to your acquaintance, an in
PRODUCTION that l am sure some OF you
will admit was not unneedcd, will now
proceed to say something concerning the