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ties of political opinions, from the most violent radicals
to the most obstinate conservatives. The answer was
always the same ; every one placed the services of our
academician above all comparison ; each man quoted,
besides, the discourses pronounced at the meeting in
which the Westminster statue was voted, as the faithful
and unanimous expression of the sentiments of the Eng-
lish nation. What did these discourses say ?

Lord Liverpool, Prime Minister of the Crown, calls
Watt, " one of the most extraordinary men that England
ever produced, one of the greatest benefactors to the
human race." He declared that " his inventions have
augmented the resources of his country and of the whole
world, to an incalculable degree." Then, considering
the question in a political point of view, he added, — " I
have lived at a time, when the success of a war depended
on the possibility of pushing our fleets out of port with-
out loss of time ; contrary winds prevailed during whole
months, and would have entirely upset the intentions of
government. Thanks to the steam-engine, such difficul-
ties have disappeared for ever." *

" Direct your attention," Sir Humphry Davy ex-
claimed, " to the metropolis of this powerful empire, to
our townis, to our villages, to our arsenals, to our manu-
factories ; examine our subterranean cavities, and the
works accomplished on the surface of the globe ; con-
template our rivers, our canals, the seas which bathe our
shores ; you will everywhere find proofs of the eternal
benefits conferred by that great man."

The illustrious President of the Royal Society also

* It should be obseryed that during the wars of which Lord Liver-
pool had any cognizance, steam had not been applied to this purpose.
— Translator.


said : " The genius exerted by Watt in his admirable
inventions, has contributed more to show the practical
utility of science, to enlarge the power of man over the
material world, to multii)ly and to spread the conven-
iences of life, than the efforts of any other man of mod-
ern times." Finally, Davy does not hesitate to place
Watt above Archimedes !

Then Huskisson, Minister of the Board of Trade,
divesting himself for a moment of the character (qualite)
of an Englishman (?), proclaims, that compared in their
bearings on the happiness of the whole human species,
Watt's inventions would still appear to him to deserve
the highest admiration. He explains in what manner
the economy of labour, the indefinite multiplication and
cheapness of industrial products, contribute to excite and
to spread knowledge. He said : " The steam-engine
is not only, in the hands of man, the most powerful
instrument they use to alter the face of the physical
world ; it acts also as a moral and irresistible lever for
pushing on the great cause of civilization."

From this point of view. Watt appeared to him in a
distinguished rank among the benefactors of humanity.
As an Englishman he does not hesitate to say that with-
out Watt's creations the British nation could not have
stood the immense expenses of its recent war with

The same idea may be observed in the discourse of
another member of Parliament, in that of Sir James
Mackintosh : see whether he expresses himself in less
positive terms. "It was the inventions of Watt that
enabled England to sustain the severest, the most dan-
gerous conflicts that she was ever engaged in." Every-
thing considered, Mackintosh declares, without hesitation,


that " no man has had more evident claim than Watt to
the homage of his country, to the respect and venei-ation
of future ages."

I will now give some numerical estimates, some num-
bers, which to my mind are more eloquent still than the
several passages which I have been quoting.

Mr. Boulton, junior, announced that in the year 1819,
the manufactory of Soho alone had already made Watt's
engines equal to the labour of a hundred thousand
horses ; that the saving arising from the substitution of
these machines for animal power amounted to seventy-
five millions of francs (three millions sterling) per an-
num. In England and Scotland at that time, there
existed upwards of ten thousand steam-engines. They
did the work of five hundred thousand horses, or of
between three and four millions of men ; with an annual
saving of three or four hundred millions of francs (twelve
or sixteen miUions sterling). And these results must by
this time be more than doubled.

I have thus abridged what was thought of Watt by
the ministers, the statesmen, the learned men, and the
industrial men — the best able to appreciate him. Gen-
tlemen, the creator of six or eight millions of workmen,
indefatigable and assiduous workmen, among whom
authority will never have to repress combination or riot,
workmen on five centimes per day (one half-penny) ;
this man, who, by brilliant inventions, gave England the
means of maintaining a desperate struggle, during which
its very nationahty was at stake, this new Archimides,
this benefactor of the whole human race, whose memory
will be blessed by future generations — what was done to
honour him during his life ?

The peerage is in England the first of its dignities, its


highest reward. You will naturally suppose that Watt
was made a peer.

Such a thing was not even thought of !

To speak honestly, so much the worse for the peer-
age, which would have been honoured by the name of
Watt !

Such a neglect, however, in a nation so justly proud
of its great men, might well astonish me. And when I
inquired the cause, what do you think they answered ?
" The dignities of which you speak are reserved for
officers of the army and navy, for influential orators in
the House of Commons, for members of the nobility.
It is not the fashion (I do not invent, I quote precisely,)
it is not the custom, to grant them to learned men, to
literary men, to artists, to engineers ! " I know well
that it was not the fashion under Qyeen Anne, since
Newton was not made a peer of England.* But after
a century and a half of progress in science and in phi-
losophy, when each of us during the short course of his
life has seen so many wandering kings cast off, proscribed,
succeeded on their thrones by soldiers without genealogy,
sons of their sword, was it not allowable to think that it
had become obsolete to divide men into folds ; that none
would any longer say to their faces, as in the inflexible
code of the Pharaohs — "Wliatever be your services,

* The whole truth should have been told. Newton, though unfor-
tunatel}' not made a peer, was never hidden under a bushel. He was
knighted by Queen Anne, and courted by King George I. and by the
Princess of Wales, afterwards Queen Caroline. He was President of
the Royal Society, a Member of Parliament, a Master of the Mint;
and at his interment the pall was supported by the Lord High Chan-
cellor, the Dukes of Montrose and Roxburgh, and the Earls of Pem-
broke, Sussex, and Macclesfield. Moreover, our author seems to
have excluded the host of lawyer-peers from the class " learned
men." — Translator.


your virtues, your knowledge, not one of you shall over-
step the boundary of your caste ; " that a foolish custom,
in short, since such a custom exists, should no longer
blot the institutions of a great nation !

Let us trust to the future. A time will come when the
science of destruction will bow before the arts of peace ;
when the genius which multiplies our powers, which
creates new products, which spreads comfort among
masses of people, will occupy that place in the general
esteem of mankind, that reason and good sense assign to
it already.

"Watt will then appear before the grand jury of the
two worlds. Every one will see him, aided by his steam-
engine, penetrate in a few weeks into the bowels of the
earth to depths where, before him, we could not have
arrived without a century's most painful efforts ; he w'll
dig spacious galleries there, and will clear them in a
few minutes of the immense volumes of w^ater that used
to inundate them daily ; he will drag from a virgin soil
the inexhaustible riches that nature deposited there.

Uniting delicacy with power, Watt will twist with
equal success the enormous strands of the colossal cable
by which the man-of-war moors itself in the midst of the
chafed ocean — and the microscopic filaments of that lace,
of that aerial web, which forms so favourite a portion of
the various dresses introduced by fashion.

A few oscillations of this same machine will restore to
agriculture vast swamps ; thus fertile countries will be
rescued from the pei-iodical and fatal miasma that used
to be fostered there by the burning summer-suns.

The great mechanical powers that we used to have to
seek in mountainous regions, at the foot of large water-
falls, now, thanks to Watt's discovery, will arise at will,


in a compact form, and without annoyance in the midst
of towns, in every floor of a house.

The intensity of this power will vaiy according to the
will of the mechanic ; it will not depend as formerly on
the most inconstant of natural causes : on atmospheric

The various branches of a manufactory can be united
in one common area, and under one roof.

The industrial products, whilst undergoing improve-
ment, will also be reduced in price.

The population well-fed, well-dressed, well-warmed,
will increase rapidly ; it will cover every part of the
territory with elegant habitations ; even those parts that
might justly be called the steppes of Europe, and which
from the aridity of ages seemed to be condemned to re-
main the exclusive domain of wild beasts.

In a few years hamlets will become important cities :
in a few years boroughs, such as Birmingham, where
there used to be scarcely thirty streets, will rise to be
ranked among the largest cities, the handsomest and the
richest of a powerful kingdom.

Installed on board ship, the steam-engine will replace
a hundi-edfold the efforts of the triple, of the quadruple
banks of rowers, from whom our ancestors required a
degree of labour classed among the punishments of the
worst criminals.

By the aid of a few tons of coals, man will conquer
the elements ; he will laugh at calms, at contrary winds,
at storms.

Passages from one country to another will become
more rapid ; the time of the steamboat's arrival can be
foretold as correctly as that of a public land conveyance ;
you will no more go to the sea-shore for weeks, or even

20 *


whole months, your heart a prey to cruel anguish, seeking
with an anxious eye along the horizon, for the uncertain
glimpse of the ship that is to restore to you a father, a
mother, a brother, or a friend.

To conclude, the steam-engine, dragging in its train
some thousands of travellers, will run along the railways
much faster than the best blood horse bearing only his
light jockey along the race-course.

There, Gentlemen, is a very brief sketch of the bene-
fits bequeathed to the world by the machine, the germs
of which Papin had deposited in his works, and which,
after so many ingenious efforts, Watt has brought to an
admirable perfection.* Posterity certainly will not weigh

* A trnnslator sliould not, perhaps, enter the lists, but he may in-
trude a remark. It is difficult to opine why our author should bestir
himself so eagerly to give Watt the composition of water, and yet im-
pair his grand claim to universal homage by foisting in the names of
Eivanlt, De Caus, and others as inventors: the early engines were
mere toys and pumps, and therefore foreign to tlie marvellous and
almost animated machine which is now in use. Some of Watt's ex-
cogitations and contrivances, the product of lengthy intellectual
struggles, are slurred over, while others are not even alluded to; and
the difficulties he had to combat with in metallurgy are altogether

We ought to be cautious in attaching an undue value to mere saga-
cious surmises, unsupported by legitimate proof; for notions may arise
without being brought to bear; and simultaneous ideas may be formed
without the parties being indebted to each other. M. Arago cannot
tell whether De Caus actually made an engine ; but surely he ought,
as a self- constituted historical umpire, to have consulted the published
Travels of Cos7no III. ( Grand Duke of Tuscany) in England, in the reign
of Charles II., and he would there have found that the Marquis of
Worcester actually did make one (see note to page 378). Now for all
that is admirable in the structure of the mighty piece of mechanism,
and really marvellous in its application, Watt was not a mere im-
prover, but a highly-gifted inventor. We therefore insist that, to all
its useful intents and purposes, the present Steam-engine is a British
production. Thus in transcendental science, although preceding and


them with other labours that have been too much vaunted ;
and whose real influence at the tribunal of I'eason, will
always remain circumscribed to a circle of a few individ-
uals, and a short compass of years.

They used formerly to appeal to the age of Augustus,
then to the age of Louis XIV. Some eminent minds
have already maintained that it would be justice to speak
of the age of Voltaire, of Rousseau, of Montesquieu.
As to myself, I do not hesitate to announce, that when to
the immense services already rendered by the steam-
engine, all the wonders are added that it still promises,
grateful nations will also speak of the ages of Papin and
of Watt !


A biography of Watt, intended to make part of our
collection of memoirs, would certainly be incomplete if
it did not contain a list of the academical titles with which
the illustrious engineer was invested. This list, more-
over, will occupy only a few lines : —

contemporary philosophers had made conjectures on the subject that
did not difter widely from truth, Newton, by an inductive ascent
through a train of abstruse investigations to its principle, and thereby
detecting and expounding its laws, is justly recognized as the author
of the sublime hypothesis of Gravitation. Who will deny to
Herschel the merit of discovering the planet Uranus, since Flamsteed
had previously observed it as a star ? Or still later, because some
philosophers thought that there might exist a planet exterior to
Uranus, who would deny the palm to those whose energies were
awakened by the orbital tremblings of that outer body to the splendid
discovery of Neptune V In reality, De Caus, Worcester, and Fapin
may be placed with respect to Watt, as Gilbert, Kepler, and Hooke
are to Newton; or as Lambert, De Zach, and Bode will be to Le
Vcrrier and Atiams. — Translalor.


Watt became :

Fellow of the Royal Society of

Edinburgh in 1784 ;

Fellow of the Royal Society of

London in 1785 ;

Fellow of the Society of Batavia . in 1787 ;
By a spontaneous and unanimous

vote, the Senate of the Uni-
versity of Glasgow awarded to

Watt the honorary degree of

Doctor of Laws . . . . in 1806 ;
Correspondent of the Institute . . in 1808 ;
The Academy of Sciences of the

Listitute paid Watt the highest

honour there is in its awaixls,

by naming him one of its

eight Foreign Associates . . in 1814.



There is no doubt that in England, at least, tke researches
respecting the composition of water originated in Warltire's
experiments related in the fifth volume of Priestley.* Caven-
dish cites them expressly as having given him the idea of his
work {Phil. Trans. 1784, p. 126). Warltire's experiments con-
sisted in the combustion of a mixture of oxygen and hydrogen,
by means of the electric spark, and in closed vessels. Two re-
sults wei'e reported therefrom: 1. a perceptible loss of weight;
2. the precipitation of some humidity on the sides of the vessels.

Watt inadvertently said in the note to page 332, of his
Memoir (Phil. Trans. 1784), that the aqueous precipitation
was observed for the first time by Cavendish ; but Cavendish
himself declares, p. 127, that Warltire had perceived the slight
aqueous deposit, and quotes on this subject Priestley's fifth
volume. Cavendish could not ascertain any loss of weight.
He remarks that Priestley's essays had led him to the same
result,-\ and adds that the humidity which was deposited con-

* Warltire's letter, dated Birmingham, 18th AprU, 1781, was pub-
lished by Dr. Priestley in the second volume of his Experiments and
Observations relating to various l^ranches of Natural Philosophy^ loiih a
continuation of the Observations on Air, forming, in short, tlie fifth
volume of the Experiments and Observations on different Kinds oj" Air,
published at Birmingham in 1781. — {Note by Mr. \Valt,jun.)

t The note by Mr. Cavendish to p. 127, seems to imply that Priest-


tained no impurity (literally no particle of soot or of sooty
matter). After a great number of trials, Cavendish perceived
that if a mixture of common and of inflammable air is ignited,
a mixture formed of 1000 measures of the former and 423 of
the latter, " about one fifth of the common and nearly the

ley had not perceived any loss of weight; but I do not find this asser-
tion anywhere in the Memoirs of the Birmingham chemist.

Warltire's earliest experiments on the combustion of gas were made
in a copper globe which weighed 398 grammes, and the volume was
170 centilitres. The author wished " to decide whether heat is, or is
not heavy."

Warltire first describes the method of mixing the gases, and of ad-
justing the scales; he then says, "I always carefully weighed the
vessel filled with common air, so that the difference of weight after
the addition of the inflammable air enabled me to judge whether the
mixture had been efiected in the desired proportions. The passage of
the electric spark rendered the globe hot. After it had cooled by ex-
posure to the air of the room, I suspended it again on the scales. I
alwaj-s found a loss of weight, but there were differences between oae
experiment and another. The mean loss was 129 milligrammes."

Warltire continues as follows: "I have exploded my airs in glass
vessels since I saw you recently do so yourself (Priestley), and I have
observed, as you did, that however dry and clean the vessel might
be before the explosion, it was afterwards covered with dew and a
black sooty substance.'"

la comparing all these claims, does not the merit of having first
perceived tlie dew belong to Priestley ?

In the few remarks that Priestley has added to his correspondent's
letter, he confirms the loss of weight, and adds, " Still, I do not think
that the bold opinion of the latent heat of bodies entering as a sensible
part of their weight, can be admitted without making experiments on a
larger scale. If that is confirmed it will be a very remarkable fact,
and one that will do infinite credit to Warltire's sagacity."

And Priestley continues, " We must say also, that at the moment
when he (Warltire) saw the dew on the interior surface of the closed
glass vessel, he said that it confirmed an opinion which he had long
entertained, the opinion that common air parts with its humidity when
it is phlogisticated."

It is evident then that Warltire explained the dew by the simple
mechanical precipitation of the hygrometric water contained in cam-
mon air. — (Note by Mr. \Vatt,jun.)


whole of the inflammable air lose their elasticity, and form by

their condensation the dew that covers the glass On

examining the dew, Cavendish found that it consisted of pure
■water He thence concluded that nearly all the in-
flammable air and about one sixth of the common air are
turned into pure water."

In a similar way, Cavendish burned a mixture of inflam-
mable air, and dephlogisticated air (or hydrogen and oxygen) ;
the fluid that was jirecipitated was always more or less acid,
according as the gas burned with the inflammable air contained
more or less phlogiston. The acid thus engendered was nitric

Mr. Cavendish ascertained that nearly the whole of the in-
flammable air and the dephlogisticated air are converted into
pure water ; also, that if those airs could be obtained in a per-
fectly pure state, the whole would be condensed. If common
air and inflammable air do not yield any acid when they are
burnt, it is, according to our author, because the heat is not
then intense.

Cavendish declares that his experiments, except in as far as
they relate to the acid, were made in the summer of 1781,
and that Priestley was aware of them. He adds, " One of my
friends gave some account of them to Lavoisier, in the course
of last spring (the spring of 1783), and also of the result that
I had inferred from them, that is to say, that dephlogisticated
air is water deprived of its phlogiston. But at that time, La-
voisier was so far from thinking that such a opinion was legiti-
mate, that until the moment when he determined to repeat
the experiments himself, he felt some difficulty in believing
that nearly the whole of the two airs could be converted into

The friend alluded to in the preceding passage was Dr.,
since become Sir Charles Blagden. It is a remarkable cir-
cumstance, that this passage in the work of Mr. Cavendish
should not have formed part of the original Memoir that was
presented to the Royal Society. The Memoir seems to be
written in the author's own handwriting ; but the paragraphs


134 and 135 were not there at first ; they are added, and an
indication is given as to where they belong ; the writing is no
longer that of Cavendish ; these additions are in the hand-
writing of Blagden. And it must have been he who gave all
the relative details to Lavoisier, for it is not said that Caven-
dish held any direct correspondence with him.

The date of the reading of Cavendish's Memoir was the 15th
of January, 1 784. The volume of the Philosophical Trans-
actions, of which this Memoir forms a part, did not appear till
about six months after.

Lavoisier's Memoir (volume of the Academy of Sciences for
1781)* had been read in November and December, 1783.
Various additions were made to it afterwards. The publica-
tion took place in 1 784.

This Memoir contained a description of the experiments of
June, 1783, at which Lavoisier announces that Blagden was
present. Lavoisier adds, that this English physicist informed
him " that Cavendish having already burnt inflammable air in
closed vessels, had obtained a very sensible quantity of water ;"
but he nowhere says that Blagden informed him of the con-
clusions that Cavendish had inferred from those same experi-

Lavoisier declares, in the most express manner, that the
weight of the water is equal to that of the two gases that were
ignited, unless, contrary to his own opinion, a sensible weight
be assigned to the heat and to the light that were disengaged
during the experiment.

This account does not agree with that of Blagden, which,
according to all probability, was written as a refutation to
Lavoisier's relation, after the reading of Cavendish's Memoir,
and before the volume of the Academy of Sciences had reached
England. This volume appeared in 1784, and assuredly it
could not have reached London, either when Cavendish read
his paper to the Royal Society, or still less when he wrote it.
We must remark, besides, that in the passage of Cavendish's

* The date 1781 appears to be a clericiil error for 11 Si.— Translate .

LORD brougham's APPENDIX. 473

manuscript Memoir, in the handwriting of Blagden, there is
only one communication of experiments alluded to : one com-
munication to Priestley. The experiments are there said to
have been made in 1781 ; but there is no mention of the date
of the conununication. Nor are we informed whether the con-
clusions inferred from those experiments, and which, accord-
ing to Blagden, were communicated by him to Lavoisier in the
summer of 1783, were equally included in the communication
made to Priestley. This chemist, in his Memoir written before
the month of April, 1783, read in June of the same year, and
quoted by Cavendish, says nothing of the theory of the latter,
although he quotes experiments.

Several propositions flow from the preceding facts : —

1. Cavendish, in the Memoir that was read to the Royal

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