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Count Rumford


Benjamin Thompson, like Franklin, was a native of Massachusetts, his

ancestors for several generations having been yeomen in that province,

and descendants of the first colonists of the Bay. In the diploma of

arms granted him when he was knighted by George III., he is described

as "son of Benjamin Thompson, late of the province of Massachusetts

Bay, in New England, gent." He was born in the house of his

grandfather, Eb
nezer Thompson, at Woburn, Massachusetts, on March 26,

1753. His father died at the age of twenty-six, on November 7, 1754,

leaving the infant Benjamin and his mother to the care of the

grandparents. The widow married Josiah Pierce, junior, in March, 1756,

and with her child, now a boy of three, went to live in a house but a

short distance from her former residence.



Young Thompson appears to have received a sound elementary education

at the village school. From some remarks made by him in after years

to his friend, M. Pictet, it has been inferred that he did not receive

very kind treatment at the hands of his stepfather. It is clear,

however, that the most affectionate relationships always obtained

between him and his mother, and the latter appears to have had no

cause to complain of the treatment she received from her second

husband, with whom she lived to a very good old age. That Thompson in

early boyhood developed some tendencies which did not meet with ready

sympathy from those around him is, however, equally clear. His

guardians destined him for a farmer, like his ancestors, and his

experiments in mechanics, which took up much of his playtime and in

all probability not a few hours which should have been devoted to less

interesting work, were not regarded as tending towards the end in

view. Hence he was probably looked upon as "indolent, flighty, and

unpromising." Later on he was sent to school in Byfield, and in 1764,

at the age of eleven, "was put under the tuition of Mr. Hill, an able

teacher in Medford, a town adjoining Woburn." At length, his friends

having given up all hope of ever making a farmer of the boy, he was

apprenticed, on October 14, 1766, to Mr. John Appleton, of Salem, an

importer of British goods and dealer in miscellaneous articles. He

lived with his master, and seems to have done his work in a manner

satisfactory on the whole, but there is evidence that he would, during

business hours, occupy his spare moments with mechanical contrivances,

which he used to hide under the counter, and even ventured

occasionally to practise on his fiddle in the store. He stayed with

Mr. Appleton till the autumn of 1769, and during this time he attended

the ministry of the Rev. Thomas Barnard. This gentleman seems to have

taken great interest in the boy, and to have taught him mathematics,

so that at the age of fifteen he was able "to calculate an eclipse,"

and was delighted when the eclipse commenced within six seconds of his

calculated time. Thompson, while an apprentice, showed a great faculty

for drawing and designing, and used to carve devices for his friends

on the handles of their knives or other implements. It was at this

time he constructed an elaborate contrivance to produce perpetual

motion, and on one evening it is said that he walked from Salem to

Woburn, to show it to Loammi Baldwin, who was nine years older than

himself, but his most intimate friend. Like many other devices

designed for the same purpose, it had only one fault--it wouldn't go.



It was in 1769, while preparing fireworks for the illumination on the

abolition of the Stamp Act, that Thompson was injured by a severe

explosion as he was grinding his materials in a mortar. His note-book

contained many directions for the manufacture of fireworks.



During Thompson's apprenticeship those questions were agitating the

public mind which finally had their outcome in the War of

Independence. Mr. Appleton was one of those who signed the agreement

refusing to import British goods, and this so affected the trade of

the store that he had no further need for the apprentice. Hence it was

that, in the autumn of 1769, Thompson went to Boston as

apprentice-clerk in a dry goods store, but had to leave after a few

months, through the depression in trade consequent on the

non-importation agreement.



His note-book, containing the entries made at this time, comprised

several comic sketches very well drawn, and a quantity of business

memoranda which show that he was very systematic in keeping his

accounts. His chief method of earning money, or rather of making up

the "Cr." side of his accounts, was by cutting and cording wood. A

series of entries made in July and August, 1771, show the expense he

incurred in constructing an electrical machine. It is not easy to

determine, from the list of items purchased, the character of the

machine he constructed; but it is interesting to note that the price

in America at that time of nitric acid was 2s. 6d. per ounce; of

lacquer, 40s. per pint; of shellac, 5s. per ounce; brass wire,

40s. per pound; and iron wire, 1s. 3d. per yard. The nature of the

problems which occupied his thoughts during the last year or two of

his business life are apparent in the following letters:--



Woburn, August 16, 1769.



Mr. Loammi Baldwin,



SIR,



Please to inform me in what manner fire operates upon clay to

change the colour from the natural colour to red, and from red

to black, etc.; and how it operates upon silver to change it to

blue.



I am your most humble and obedient servant,



BENJAMIN THOMPSON



God save the king.





Woburn, August, 1769.



Mr. Loammi Baldwin,



SIR,



Please to give the nature, essence, beginning of existence, and

rise of the wind in general, with the whole theory thereof, so

as to be able to answer all questions relative thereto.



Yours,



BENJAMIN THOMPSON.



This was an extensive request, and the reply was probably not

altogether satisfactory to the inquirer. On the back of the above

letter was written:--



Woburn, August 15, 1769.



SIR,



There was but few beings (for inhabitants of this world) created

before the airy element was; so it has not been transmitted down

to us how the Great Creator formed the matter thereof. So I

shall leave it till I am asked only the Natural Cause, and why

it blows so many ways in so short a time as it does.



Thompson appears now to have given up business and commenced the study

of medicine under Dr. Hay, to whom for a year and a half he paid

forty shillings per week for his board. During this time he paid part

of his expenses by keeping school for a few weeks consecutively at

Wilmington and Bradford, and another part was paid by cords of wood.

His business capacity, as well as his dislike of ordinary work, is

shown by some arrangements which he made for getting wood cut and

corded at prices considerably below those at which he was himself paid

for it. His note-book made at this time contains, besides business

entries, several receipts for medicines and descriptions of surgical

operations, in some cases illustrated by sketches. In his work he was

methodical and industrious, and the life of a medical student suited

his genius far better than that of a clerk in a dry goods store. When

teaching at Wilmington he seems to have attracted attention by the

gymnastic performances with which he exercised both himself and his

pupils. While a student with Dr. Hay, he attended some of the

scientific lectures at Harvard College. The pleasure and profit which

he derived from these lectures are sufficiently indicated by the fact

that forty years afterwards he made the college his residuary legatee.



Thompson won such a reputation as a teacher during the few weeks that

he taught in village schools in the course of his student life, that

he received an invitation from Colonel Timothy Walker to come to

Concord, in New Hampshire, on the Merrimack, and accept a permanent

situation in a higher grade school. It was from this place that he

afterwards took his title, for the early name of Concord was Rumford,

and the name was changed to Concord "to mark the restoration of

harmony after a long period of agitation as to its provincial

jurisdiction and its relation with its neighbours."



The young schoolmaster of Concord was soon on very intimate terms with

the minister of the town, the Rev. Timothy Walker,[5] a man who was so

much respected that he had thrice been sent to Britain on diplomatic

business. Mr. Walker's daughter had been married to Colonel Rolfe, a

man of wealth and position, and, with the exception of the Governor of

Portsmouth, said to have been the first man in New Hampshire to drive

a curricle and pair of horses. Thompson soon married--or, as he told

Pictet, was married to--the young widow. Whatever may have been

implied by this other way of putting the question, there is no doubt

that Thompson always had the greatest possible respect for his

father-in-law, and ever remembered him with sincere gratitude. The

fortunes of the gallant young schoolmaster now appeared to be made;

when the engagement was settled, the carriage and pair were brought

out again, and the youth was attired in his favourite scarlet as a man

of wealth and position. In this garb he drove to Woburn, and

introduced his future wife to his mother, whose surprise can be better

imagined than described.



[Footnote 5: Father of the colonel.]



The exact date of Thompson's marriage is not known. His daughter

Sarah, afterwards Countess of Rumford, was born in the Rolfe mansion

on October 18, 1774. It is needless to say that the engagement to Mrs.

Rolfe terminated the teaching at the school.



Thompson now had a large estate and ample means to improve it. He gave

much attention to gardening, and sent to England for garden seeds. In

some way he attracted the attention of Governor Wentworth, the

Governor of Portsmouth, who invited him to the Government House, and

was so taken with the former apprentice, medical student, and

schoolmaster, that he gave him at once a commission as major. This

appointment was the cause of the misfortunes which almost

immediately began to overtake him. He incurred the jealousy of his

fellow-officers, over whom he had been appointed, and he failed to

secure the confidence of the civilians of Concord.



Public feeling in New England was very much excited against the mother

country. Representations were sent to the British Government, but

appeared to be treated with contempt. Very many of these documents

were found, after the war was over, unopened in drawers at the

Colonial Office. British ministers appeared to know little about the

needs of their American dependencies, and relations rapidly became

more and more strained. The patriots appointed committees to watch

over the patriotism of their fellow-townsmen, and thus the freedom of

a free country was inaugurated by an institution bordering in

character very closely upon the Inquisition; and the Committees of

Correspondence and Safety accepted evidence from every spy or

eavesdropper who came before them with reports of suspected persons.

Thompson was accused of "Toryism;" the only definite charge against

him being that he had secured remission of punishment for some

deserters from Boston who had for some time worked upon his estate. He

was summoned before the Committee of Safety, but refused to make any

confession of acts injurious to his country, on the ground that he had

nothing to confess. His whole after-life shows that his sympathies

were very much on the side of monarchy and centralization, but at this

time there appears to have been no evidence that could be brought

against him. The populace, however, stormed his house, and he owed his

safety to the fact that he had received notice of their intentions,

and had made his escape a few hours before. This was in November,

1774. Thompson then took refuge at Woburn, with his mother, but the

popular ill feeling troubled him here, so that his life was one of

great anxiety.



While at Woburn, his wife and child joined him, and stayed there for

some months. At length he was arrested and confined in the town upon

suspicion of being inimical to the interests of his country. When he

was brought before the Committee of Inquiry, there was no evidence

brought against him. Major Thompson then petitioned to be heard

before the Committee of the Provincial Congress at Washington. This

petition he entrusted to his friend Colonel Baldwin to present. The

petition was referred by the committee to Congress, by whom it was

deferred for the sake of more pressing business. At length he secured

a hearing in his native town, but the result was indecisive, and he

did not obtain the public acquittal that he desired, though the

Committee of Correspondence found that the "said Thompson" had not "in

any one instance shown a disposition unfriendly to American liberty;

but that his general behaviour has evinced the direct contrary; and as

he has now given us the strongest assurances of his good intentions,

we recommend him to the friendship, confidence, and protection of all

good people in this and the neighbouring provinces." This decision,

however, does not appear to have been made public; and Thompson, on

his release, retired to Charlestown, near Boston. When the buildings

of Harvard College were converted into barracks, Major Thompson

assisted in the transfer of the books to Concord. It is said that,

after the battle of Charlestown, Thompson was introduced to General

Washington, and would probably have received a commission under him

but for the opposition of some of the New Hampshire officers. He

afterwards took refuge in Boston, and it does not appear that he ever

again saw his wife or her father. His daughter he did not see again

till 1796, when she was twenty-two years of age. On March 24, 1776,

General Washington obliged the British troops to evacuate Boston;

Thompson was the first official bearer of this intelligence to London.

Of course, his property at Concord was confiscated to the commonwealth

of Massachusetts, and he himself was proscribed in the Alienation Act

of New Hampshire, in 1778.



When Thompson reached London with the intelligence of the evacuation

of Boston, Lord George Germaine, the Secretary for War, saw that he

could afford much information which would be of value to the

Government. An appointment was soon found for him in the Colonial

Office, and afterwards he was made Secretary of the Province of

Georgia, in which latter capacity, however, he had no duties to

fulfil. Throughout his career in the Colonial Office he remained on

very intimate terms with Lord George Germaine, and generally

breakfasted with him. In July, 1778, he was guest of Lord George at

Stoneland Lodge, and here, in company with Mr. Ball, the Rector of

Withyham, he undertook experiments "to determine the most advantageous

situation for the vent in firearms, and to measure the velocities of

bullets and the recoil under various circumstances."



The results of these investigations procured for him the friendship of

Sir Joseph Banks, the President of the Royal Society, and Thompson was

not the man to lose opportunities for want of making use of them. In

1779 he was elected a Fellow of the Royal Society, "as a gentleman

well versed in natural knowledge and many branches of polite

learning." In the same year he went for a cruise in the Victory with

Sir Charles Hardy, in order to pursue his experiments on gunpowder

with heavy guns. Here he studied the principles of naval artillery,

and devised a new code of marine signals. In 1780 he was made

Under-Secretary of State for the Northern Department, and in that

capacity had the oversight of the transport and commissariat

arrangements for the British forces.



On the defeat of Cornwallis, Lord George Germaine and his department

had to bear the brunt of Parliamentary dissatisfaction. Lord George

resigned his position in the Government, and was created Viscount

Sackville. He had, however, previously conferred on Thompson a

commission as lieutenant-colonel in the British army, and Thompson,

probably foreseeing the outcome of events and its effect on the

Ministry, was already in America when Lord George resigned. He had

intended landing at New York, but contrary winds drove him to

Charlestown. It is needless to trace the sad events which preceded the

end of the war. It was to be expected that many bitter statements

would be made by his countrymen respecting Thompson's own actions as

colonel commanding a British garrison, for at length he succeeded in

reaching Long Island, and taking the command of the King's American

Dragoons, who were there awaiting him. The spirit of war always acts

injuriously on those exposed to its influence, and Lieutenant-Colonel

Thompson in Long Island was doubtless a very different man from that

which we find him to have been before and after; nor were the months

so spent very fruitful in scientific work.



In 1783, before the final disbanding of the British forces, Thompson

returned to England, and was promoted to the rank of colonel, with

half-pay for the rest of his life. Still anxious for military service,

he obtained permission to travel on the Continent, in hopes of serving

in the Austrian army against the Turks. He took with him three English

horses, which rendered themselves very objectionable to his

fellow-travellers while crossing the Channel in a small boat. Thompson

went to Strasbourg, where he attracted the attention of the Prince

Maximilian, then Field-Marshal of France, but afterwards Elector of

Bavaria. On leaving Strasbourg, the prince gave him an introduction to

his uncle, the Elector of Bavaria. He stayed some days at Munich, but

on reaching Vienna learned that the war against the Turks would not be

carried on, so he returned to Munich, and thence to England.



M. Pictet gives the following as Rumford's account of the manner in

which he was cured of his passion for war:--



"'I owe it,' said he to me, one day, 'to a beneficent Deity, that I

was cured in season of this martial folly. I met, at the house of the

Prince de Kaunitz, a lady, aged seventy years, of infinite spirit and

full of information. She was the wife of General Bourghausen. The

emperor, Joseph II., came often to pass the evening with her. This

excellent person conceived a regard for me; she gave me the wisest

advice, made my ideas take a new direction, and opened my eyes to

other kinds of glory than that of victory in battle.'"



If the course in life which Colonel Thompson afterwards took was due

to the advice of this lady, she deserves a European reputation. The

Elector of Bavaria, Charles Theodore, gave Thompson a pressing

invitation to enter his service in a sort of semi-military and

semi-civil capacity, to assist in reorganizing his dominions and

removing the abuses which had crept in. Before accepting this

appointment, it was necessary to obtain the permission of George III.

The king not only approved of the arrangement, but on February 23,

1784, conferred on the colonel the honour of knighthood. Sir Benjamin

then returned to Bavaria, and was appointed by the elector colonel of

a regiment of cavalry and general aide-de-camp. A palatial residence

in Munich was furnished for him, and here he lived more as a prince

than a soldier. It was eleven years before he returned, even on a

visit, to England, and these years were spent by him in works of

philanthropy and statesmanship, to which it is difficult to find a

parallel. At one time he is found reorganizing the military system of

the country, arranging a complete system of military police, erecting

arsenals at Mannheim and Munich; at another time he is carrying out

scientific investigations in one of these arsenals; and then he is

cooking cheap dinners for the poor of the country.



One great evil of a standing army is the idleness which it develops in

its members, unfitting them for the business of life when their

military service is ended. Thompson commenced by attacking this evil.

In 1788 he was made major-general of cavalry and Privy Councillor of

State, and was put at the head of the War Department, with

instructions to carry out any schemes which he had developed for the

reform of the army and the removal of mendicity. Four years after his

arrival in Munich he began to put some of his plans into operation.

The pay of the soldiers was only threepence per day, and their

quarters extremely uncomfortable, while their drill and discipline

were unnecessarily irksome. Thompson set to work to make "soldiers

citizens and citizens soldiers." The soldier's pay, uniform, and

quarters were improved; the discipline rendered less irksome; and

schools in which the three R's were taught were connected with all the

regiments,--and here not only the soldiers, but their children as well

as other children, were taught gratuitously. Not only were the

soldiers employed in public works, and thus accustomed to habits of

industry, while they were enlivened in their work by the strains of

their own military bands, but they were supplied with raw material of

various kinds, and allowed, when not on duty, to manufacture various

articles and sell them for their own benefit--an arrangement which in

this country to-day would probably raise a storm of opposition from

the various trades. The garrisons were made permanent, so that

soldiers might all be near their homes and remain there, and in time

of peace only a small portion of the force was required to be in

garrison at any time, so that the great part of his life was spent by

each soldier at home. Each soldier had a small garden appropriated to

his use, and its produce was his sole property. Garden seeds, and

especially seed potatoes, were provided for the men, for at that time

the potato was almost unknown in Bavaria. Under these circumstances a

reform was quickly effected; idle men began to take interest in their

gardens, and all looked on Sir Benjamin as a benefactor.



Having thus secured the co-operation of the army, Thompson determined

to attack the mendicants. The number of beggars may be estimated from

the fact that in Munich, with a population of sixty thousand, no less

than two thousand six hundred beggars were seized in a week. In the

towns, they possessed a complete organization, and positions of

advantage were assigned in regular order, or inherited according to

definite customs. In the country, farm labourers begged of travellers,

and children were brought up to beggary from their infancy. Of course,

the evils did not cease with simple begging. Children were stolen and

ill treated, for the purpose of assisting in enlisting sympathy, and

the people had come to regard these evils as inevitable. Thompson

organized a regular system of military patrol through every village of

the country, four regiments of cavalry being set apart for this work.

Then on January 1, 1790, when the beggars were out in full force to

keep their annual holiday, Thompson, with the other field officers and

the magistrates of the city, gave the signal, and all the beggars in

Munich were seized upon by the three regiments of infantry then in

garrison. The beggars were taken to the town hall, and their names and

addresses entered on lists prepared for the purpose. They were ordered

to present themselves next day at the "military workhouse," and a

committee was appointed to inquire into the condition of each, the

city being divided into sixteen districts for that purpose. Relieved

of an evil which they had regarded as inevitable, the townspeople

readily subscribed for the purpose of affording systematic relief,

while tradesmen sent articles of food and other requisites to "the

relief committee." In the military workhouse the former mendicants

made all the uniforms for the troops, besides a great deal of clothes

for sale in Bavaria and other countries. Thompson himself fitted up

and superintended the kitchen, where food was daily cooked for between

a thousand and fifteen hundred persons; and, under Sir Benjamin's

management, a dinner for a thousand was cooked at a cost for fuel of

fourpence halfpenny--a result which has scarcely been surpassed in

modern times, even at Gateshead.



That Thompson's work was appreciated by those in whose interest it was

undertaken is shown by the fact that when, on one occasion, he was

dangerously ill, the poor of Munich went in public procession to the

cathedral to pray for him, though he was a foreigner and a Protestant.

Perhaps it may appear that his philanthropic work has little to do

with physical science; but with Thompson everything was a scientific

experiment, conducted in a truly scientific manner. For example, the

lighting of the military workhouse afforded matter for a long series

of experiments, described in his papers on photometry, coloured

shadows, etc. The investigations on the best methods of employing fuel

for culinary purposes led to some of his most elaborate essays; and

his essay on food was welcomed alike in London and Bavaria at a time

of great scarcity, and when famine seemed impending.



The Emperor Joseph was succeeded by Leopold II., but during the

interregnum the Elector of Bavaria was Vicar of the Empire, and he

employed the power thus temporarily placed in his hands in raising Sir

Benjamin to the dignity of Count of the Holy Roman Empire, with the

order of the White Eagle, and the title which the new count selected

was the old name of the village in New England where he had spent the

two or three years of his wedded life.



In 1795 Count Rumford returned to England, in order to publish his

essays, and to make known in this country something of the work in

which he had been engaged. Soon after his arrival he was robbed of

most of his manuscripts, the trunk containing them being stolen from

his carriage in St. Paul's Churchyard. On the invitation of Lord

Pelham, he visited Dublin, and carried out some of his improvements in

the hospitals and other institutions of that city. On his return to

London he fitted up the kitchen of the Foundling Hospital.



Lady Thompson lived to hear of her husband's high position in Bavaria,

but died on January 29, 1792. When Rumford came to London in 1795, he

wrote to his daughter, who was then twenty-one years of age, to meet

him there, and on January 29, 1796, she started in the Charlestown,

from Boston. She remained with her father for more than three years,

and her autobiography gives much information respecting the count's

doings during this time.



While in London, Count Rumford attained a high reputation as a curer

of smoky chimneys. One firm of builders found full employment in

carrying out work in accordance with his instructions; and in his

hotel at Pall Mall he conducted experiments on fireplaces. He

concluded that the sides of a fireplace ought to make an angle of 135 deg.

with the back, so as to throw the heat straight to the front; and that

the width of the back should be one-third of that of the front

opening, and be carried up perpendicularly till it joins the breast.

The "Rumford roaster" gained a reputation not less than that earned

by his open fireplace.



It was during this stay in London that Rumford presented to the Royal

Society of London, and to the American Academy of Sciences L1000 Three

per Cent. Stock, for the purpose of endowing a medal to be called the

Rumford Medal, and to be given each alternate year for the best work

done during the preceding two years in the subjects of heat and light.

He directed that two medals, one in gold and the other in silver,

should be struck from the same die, the value of the two together to

amount to L60. Whenever no award was made, the interest was to be

added to the principal, and the excess of the income for two years

over L60 was to be presented in cash to the recipient of the medal. At

present the amount thus presented is sufficient to pay the composition

fee for life membership of the Royal Society. The first award of the

medal was made in 1802, to Rumford himself. The other recipients have

been John Leslie, William Murdock, Etienne-Louis Malus, William

Charles Wells, Humphry Davy, David Brewster, Augustin Jean Fresnel,

Macedonio Melloni, James David Forbes, Jean Baptiste Biot, Henry Fox

Talbot, Michael Faraday, M. Regnault, F. J. D. Arago, George Gabriel

Stokes, Neil Arnott, M. Pasteur, M. Jamin, James Clerk Maxwell,

Kirchoff, John Tyndall, A. H. L. Fizeau, Balfour Stewart, A. O. des

Cloiseaux, A. J. Angstroem, J. Norman Lockyer, P. J. C. Janssen, W.

Huggins, Captain Abney.



In the summer of 1796 Rumford and his daughter left England to return

to Munich. On account of the war, they were obliged to go by sea to

Hamburg; whence they drove to Munich, where the count was anxiously

expected, political troubles having compelled the elector to leave the

city. After the battle of Friedburg, the Austrians retired to Munich,

and, finding the gates of the city closed, they fortified

themselves on an eminence overlooking the city, and, through some

misunderstanding with the local authorities, the Austrian general

threatened to attack the city if any Frenchman should be allowed to

enter. Rumford took supreme command of the Bavarian forces, and so

gained the respect of the rival generals that neither the French nor

the Austrians made any attempt to enter the city. The large number of

soldiers now in Munich gave Rumford a good opportunity to exercise his

skill in cooking on a large scale, and this he did, adding to the

comfort of the soldiers and reducing the cost of the commissariat. On

the return of the elector, Miss Sarah was made a countess, and

one-half of her father's pension was secured to her, thus providing

her with an income of about L200 per annum for life. Many of the

details of the home life and social intercourse during this period of

residence at Munich are preserved in the autobiography of the

countess, as well as accounts of excursions, including a trip by river

to Salzburg for the purpose of inspecting the salt-mines. After two

years' stay in Munich, the count was appointed Minister

Plenipotentiary from Bavaria to the Court of Great Britain. After an

unpleasant and perilous journey, he reached London, via Hamburg, in

September, 1798, but was terribly disappointed on learning that a

British subject could not be accepted as an envoy from a Foreign

Power. As he did not then wish to return to Bavaria, he purchased a

house in Brompton Row. But he had been too much accustomed to great

enterprises to be content with a quiet life, and was bound to have

some important scheme on hand. Pressing invitations were sent him to

return to America, but he preferred residence in London, and devoted

himself to the foundation of the Royal Institution, though the

countess returned to the States in August, 1799. A letter from Colonel

Baldwin to her father shortly after her return contains the following

passage:--



In the cask of fruit which your daughter and Mr. Rolfe have sent

you, there is half a dozen apples of the growth of my farm,

wrapped up in papers, with the name of Baldwin's apples

written upon them.... It is (I believe) a spontaneous production

of this country; that is, it was not originally engrafted fruit.



The history of the remaining period of Rumford's residence in London

is the early history of the Royal Institution.



For many years Rumford had had at his disposal for his philanthropic

projects all the resources of the electorate of Bavaria, and he had

done everything on a royal scale. His original plan for the Royal

Institution appears to embody to a very great extent the work of the

Science and Art Department, the City and Guilds Institute for the

Advancement of Technical Education, the National School of Cookery,

the London Society for the Extension of University Teaching, and, in

addition to all this, to have comprehended a sort of perpetual

International Health Exhibition, where every device for domestic

purposes, and especially for the improvement of the condition of the

poor, could be inspected. How all this was to be carried out with the

resources which the count expected to be able to devote to the

purpose, does not appear. Foremost among the objects of the

institution was placed the management of fire; for its promoter was

convinced that more than half the fuel consumed in the country might

be saved by proper arrangements.



The philanthropic objects with which the institution was started are

apparent from the fact that it was the Society for Bettering the

Condition of the Poor which appointed a committee to confer with

Rumford, to report on the scheme, and to raise the funds necessary for

starting the project; and one of Rumford's hopes in connection with it

was "to make benevolence fashionable." It was arranged that donors of

fifty guineas each should be perpetual proprietors of the institution;

and that subscribers should be admitted at a subscription of two

guineas per annum, or ten guineas for life. The price of a

proprietor's share was raised to sixty guineas from May 1, 1800, and

afterwards increased by ten guineas per annum up to one hundred

guineas. In a very short time there were fifty-eight fifty-guinea

subscribers, and to them Rumford addressed a pamphlet, setting forth

his scheme in detail. The following are specified as some of the

contents of the future institution:--"Cottage fireplaces and kitchen

utensils for cottagers; a farm-house kitchen with its furnishings; a

complete kitchen, with its utensils, for the house of a gentleman of

fortune; a laundry, including boilers, washing, ironing, and drying

rooms, for a gentleman's house, or for a public hospital; the most

improved German, Swedish, and Russian stoves for heating rooms and

passages." As far as possible all these things were to be seen at

work. There were also to be ornamental open stoves with fires in them;

working models of steam-engines, of brewers' boilers, of distillers'

coppers and condensers, of large boilers for hospital kitchens, and of

ships' coppers with the requisite utensils; models of ventilating

apparatus, spinning-wheels and looms "adapted to the circumstances of

the poor;" models of agricultural machinery and bridges, and "of all

such other machines and useful instruments as the managers of the

institution shall deem worthy of public notice." All articles were to

be provided with proper descriptions, with the name and address of the

maker, and the price.



A lecture-room and laboratory were to be fitted up with all necessary

philosophical apparatus, and the most eminent expounders of science

were to be engaged for the purpose of "teaching the application of

science to the useful purposes of life."



The lectures were to include warming and ventilation, the preservation

of food, agricultural chemistry, the chemistry of digestion, of

tanning, of bleaching and dyeing, "and, in general, of all the

mechanical arts as they apply to the various branches of manufacture."

The institution was to be governed by nine managers, of whom three

were to be elected each year by the proprietors; and there was also to

be a committee of visitors, the members of which should not be the

managers. The king became patron of the institution, and the first set

of officers was nominated by him. The Earl of Winchelsea and

Nottingham was President; the Earls of Morton and of Egremont and Sir

Joseph Banks, Vice-Presidents; the Earls of Bessborough, of Egremont,

and of Morton, and Count Rumford, were among the Managers; the Duke of

Bridgewater, Viscount Palmerston, and Earl Spencer the Visitors; and

Dr. Thomas Garnett was appointed first Professor of Physics and

Chemistry. The royal charter of the institution was sealed on January

13, 1800. The superintendence of the journals of the institution was

entrusted to Rumford's care. For some time the count resided in the

house in Albemarle Street, which had been purchased by the

institution, and while there he superintended the workmen and

servants.



Dr. Thomas Garnett, the first professor at the institution, was highly

respected both as a man and a philosopher, and seems to have been

everywhere well spoken of. But Rumford and he could not work together,

and his connection with the institution was consequently a short one.

Rumford was then authorized to engage Dr. Young as Professor of

Natural Philosophy, editor of the journals, and general superintendent

of the house, at a salary of L300 per annum. Shortly before this the

count's attention had been directed to the experiments on heat, made

by Humphry Davy, and on February 16, 1801, it was "resolved that Mr.

Humphry Davy be engaged in the service of the Royal Institution, in

the capacity of Assistant-Lecturer in Chemistry, Director of the

Chemical Laboratory, and Assistant-Editor of the Journals of the

Institution; and that he be allowed to occupy a room in the house, and

be furnished with coals and candles, and that he be paid a salary of

one hundred guineas per annum." In his personal appearance, Davy is

said to have been at first somewhat uncouth, and the count was by no

means charmed with him at their first interview. It was not till he

had heard him lecture in private that Rumford would allow Davy to

lecture in the theatre of the institution; but he afterwards showed

his complete confidence in the young chemist by ordering that all the

resources of the institution should be at his service. Davy dined with

Rumford at the count's house in Auteuil, when he visited Paris with

Lady Davy and Faraday, in 1813. He commenced his duties at the

institution on March 11, 1801. It was on June 15, in the same year,

that the managers having objected to the syllabus of his lectures, Dr.

Garnett's resignation was accepted; and on July 6 Dr. Young was

appointed in his stead. Dr. Young resigned after holding the

appointment only two years, as he found the duties incompatible with

his work as a physician.



Rumford's life in London now became daily more unpleasant to himself.

Accustomed, as he had been in Bavaria, to carry out all his projects

"like an emperor," it was difficult for him to work as one member of a

body of managers. One by one he quarrelled with his colleagues, and at

length left England, in May, 1802, never to return.



When distinguished men of science are placed at the head of an

institution like that which Rumford founded, there is always a

tendency for the technical teaching of the establishment to become

gradually merged into scientific research; and in this case, after

Rumford's departure, the genius of Davy gradually converted the Royal

Institution into the establishment for scientific research which it

has been for more than three quarters of a century. Probably the man

who has come nearest to realizing all that Count Rumford had planned

for his institution is the late Sir Henry Cole; but he succeeded only

through the resources of the Treasury.



On leaving England in May, 1802, Rumford went to Paris, where he

stayed till July or August, when he revisited Bavaria and remained

there till the following year, when he returned to Paris. He was again

at Munich in 1805; but under the new elector, though an old friend of

the count, relationships do not seem to have been all that they were

with his uncle, and at length the elector himself was compelled to

leave Munich, and soon after the Bavarian sovereign became a vassal of

Napoleon. On October 24, 1805, Rumford married Madame Lavoisier, a

lady of brilliant talents and ample fortune. That his position might

be nearly equal to hers, the Elector of Bavaria raised his pension to

L1200 per annum. A house, Rue d'Anjou, No. 39, was purchased for six

thousand guineas, and Rumford expended much thought and energy in

making it, with its garden of two acres, all that he could desire. But

the union was not so happy as he anticipated. The count loved quiet;

Madame de Rumford was fond of company: to the former the pleasure of

the table had no charms; the latter took delight in sumptuous

dinner-parties. As time went on, domestic affairs became more and more

unpleasant, and at length a friendly separation was agreed upon, after

they had lived together for about three years and a half. The count

then retired to a small estate which he hired at Auteuil, about four

miles from Paris. The Elector of Bavaria was crowned king on January

1, 1806, and in 1810 Rumford was again at Munich, for the purpose of

forming, at the king's request, an Academy of Arts and Sciences. At

Auteuil the count was joined by his daughter in December, 1811, her

journey having been much delayed through the capture of the vessel in

which she had taken her passage, off Bordeaux. An engraving of the

house at Auteuil, and the room in which Rumford carried on his

experiments, was published in the Illustrated London News of January

22, 1870.



While resident at Auteuil, Rumford frequently read papers before the

Institute of France, of which he was a member. He complained very much

of the jealousy exhibited by the other members with reference to any

discoveries made by a foreigner. He died in his house at Auteuil, on

August 21, 1814, in the sixty-second year of his age. In 1804 he had

made over, by deed of gift to his mother, the sum of ten thousand

dollars, that she might leave it by will to her younger children. As

before mentioned, Harvard College was his residuary legatee, and the

property so bequeathed founded the Rumford Professorship in that

institution.



Cuvier, as Secretary of the Institute, pronounced the customary eulogy

over its late member. The following passages throw some light on the

reputation in which the count was held:--



He has constructed two singularly ingenious instruments of his

own contriving. One is a new calorimeter for measuring the

amount of heat produced by the combustion of any body. It is a

receptacle containing a given quantity of water, through which

passes, by a serpentine tube, the product of the combustion; and

the heat that is generated is transmitted through the water,

which, being raised by a fixed number of degrees, serves as the

basis of the calculations. The manner in which the exterior heat

is prevented from affecting the experiment is very simple and

very ingenious. He begins the operation at a certain number of

degrees below the outside heat, and terminates it at the same

number of degrees above it. The external air takes back during

the second half of the experiment exactly what it gave up during

the first. The other instrument serves for noting the most

trifling differences in the temperature of bodies, or in the

rapidity of its changes. It consists of two glass bulbs filled

with air, united by a tube, in the middle of which is a pellet

of coloured spirits of wine; the slightest increase of heat in

one of the bulbs drives the pellet towards the other. This

instrument, which he called a thermoscope, was of especial

service in making known to him the varied and powerful influence

of different surfaces in the transmission of heat, and also for

indicating a variety of methods for retarding or hastening at

will the processes of heating and freezing....



He thought it was not wise or good to entrust to men, in the

mass, the care of their own well-being. The right, which seems

so natural to them, of judging whether they are wisely governed,

appeared to him to be a fictitious fancy born of false notions

of enlightenment. His views of slavery were nearly the same as

those of a plantation-owner. He regarded the government of China

as coming nearest to perfection, because, in giving over the

people to the absolute control of their only intelligent men,

and in lifting each of those who belonged to this hierarchy on

the scale according to the degree of his intelligence, it made,

so to speak, so many millions of arms the passive organs of the

will of a few sound heads--a notion which I state without

pretending in the slightest degree to approve it, and which, as

we know, would be poorly calculated to find prevalence among

European nations.



As for the rest, whatever were the sentiments of M. Rumford for

men, they in no way lessened his reverence for God. He never

omitted any opportunity in his works of expressing his religious

admiration of Providence, and of proposing for that admiration

by others, the innumerable and varied provisions which are made

for the preservation of all creatures; indeed, even his

political views came from his firm persuasion that princes ought

to imitate Providence in this respect by taking charge of us

without being amenable to us.



In front of the new Government offices and the National Museum in the

Maximilian Strasse, in Munich, stand, on granite pedestals, four

bronze figures, ten feet in height. These represent General Deroy,

Fraunhofer, Schelling, and Count Rumford. The statue of Rumford was

erected in 1867, at the king's private expense. In the English garden

which Rumford planned and laid out is the monument erected during his

absence in England in 1796, and bearing allegorical figures of Peace

and Plenty, and a medallion of the count.



The bare enumeration of Rumford's published papers would occupy

considerable space, but many of them have more to do with philanthropy

and domestic economy than with physics. We have seen that, when guest

of Lord George Germaine, he was engaged in experiments on gunpowder.

The experiments were made in the usual manner by firing bullets into a

ballistic pendulum, and recording the swing of the pendulum. Thompson

suggested a modification of the ballistic pendulum, attaching the

gun-barrel to the pendulum, and observing the recoil, and making

allowance for the recoil due to the discharge from the gun of the

products of combustion of the powder, the excess enabled the velocity

of the bullet to be calculated. Afterwards he made experiments on the

maximum pressure produced by the explosion of powder, and pointed out

that the value of powder in ordnance does not depend simply on the

whole amount of gas produced, but also on the rapidity of combustion.

While superintending the arsenal at Munich, Rumford exploded small

charges of powder in a specially constructed receiver, which was

closed by a plug of well-greased leather, and on this was placed a

hemisphere of steel pressed down by a 24-pounder brass cannon weighing

8081 pounds. He found that the weight of the gun was lifted by the

explosion of quantities of powder varying from twelve to fifteen

grains, and hence concluded that, if the products of combustion of the

powder were confined to the space actually occupied by the solid

powder, the initial pressure would exceed twenty thousand atmospheres.

Rumford's calculation of the pressure, based upon the bursting of a

barrel, which he had previously constructed, is not satisfactory,

inasmuch as he takes no account of the fact that the inner portions of

the metal would give way long before the outer layers exerted anything

like their maximum tension. When a hollow vessel with thick walls,

such as a gun-barrel or shell, is burst by gaseous pressure from

within, the inner layers of material are stretched to their breaking

tension before they receive much support from the outer layers; a rift

is thus made in the interior, into which the gas enters, and the

surface on which the gas presses being thus increased, the rift

deepens till the fracture is complete. In order to gain the full

strength due to the material employed, every portion of that material

should be stretched simultaneously to the extent of its maximum safe

load. This principle was first practically adopted by Sir W. G.

Armstrong, who, by building up the breech of the gun with cylinders

shrunk on, and so arranged that the tension increased towards the

exterior, availed himself of nearly the whole strength of the metal

employed to resist the explosion. Had Rumford's barrel been

constructed on this principle, he would have obtained a much more

satisfactory result.



These investigations were followed by a very interesting series of

experiments on the conducting power of fluids for heat, and, although

he pushed his conclusions further than his experiments warranted, he

showed conclusively that convection currents are the principal means

by which heat is transferred through the substance of fluids, and

described how, when a vessel of water is heated, there is generally an

ascending current in the centre, and a descending current all round

the periphery. Hence it is only when a liquid expands by increase of

temperature that a large mass can be readily heated from below. Water

below 39 deg. Fahr. contracts when heated. Rumford, in his paper, enlarges

on the bearing of this fact on the economy of the universe, and the

following extracts afford a good specimen of his style, and justify

some of the statements made by Cuvier in his eulogy:--



I feel the danger to which a mortal exposes himself who has the

temerity to undertake to explain the designs of Infinite Wisdom.

The enterprise is adventurous, but it cannot surely be improper.



The wonderful simplicity of the means employed by the Creator of

the world to produce the changes of the seasons, with all the

innumerable advantages to the inhabitants of the earth which

flow from them, cannot fail to make a very deep and lasting

impression on every human being whose mind is not degraded and

quite callous to every ingenuous and noble sentiment; but the

further we pursue our inquiries respecting the constitution of

the universe, and the more attentively we examine the effects

produced by the various modifications of the active powers which

we perceive, the more we shall be disposed to admire, adore, and

love that great First Cause which brought all things into

existence.



Though winter and summer, spring and autumn, and all the variety

of the seasons are produced in a manner at the same time the

most simple and the most stupendous (by the inclination of the

axis of the earth to the plane of the ecliptic), yet this

mechanical contrivance alone would not have been sufficient (as

I shall endeavour to show) to produce that gradual change of

temperature in the various climates which we find to exist, and

which doubtless is indispensably necessary to the preservation

of animal and vegetable life....



But in very cold countries the ground is frozen and covered with

snow, and all the lakes and rivers are frozen over in the very

beginning of winter. The cold then first begins to be extreme,

and there appears to be no source of heat left which is

sufficient to moderate it in any sensible degree.



Let us see what must have happened if things had been left to

what might be called their natural course--if the condensation

of water, on being deprived of its heat, had followed the law

which we find obtains in other fluids, and even in water itself

in some cases, namely, when it is mixed with certain bodies.



Had not Providence interfered on this occasion in a manner which

may well be considered miraculous, all the fresh water within

the polar circle must inevitably have been frozen to a very

great depth in one winter, and every plant and tree destroyed;

and it is more than probable that the region of eternal frost

would have spread on every side from the poles, and, advancing

towards the equator, would have extended its dreary and solitary

reign over a great part of what are now the most fertile and

most inhabited climates of the world!...



Let us with becoming diffidence and awe endeavour to see what

the means are which have been employed by an almighty and

benevolent God to protect His fair creation.



He then goes on to explain how large bodies of water are prevented

from freezing at great depths on account of the expansion which takes

place on cooling below 39 deg. Fahr., and the further expansion which

occurs on freezing, and mentions that in the Lake of Geneva, at a

depth of a thousand feet, M. Pictet found the temperature to be 40 deg.

Fahr.



"We cannot sufficiently admire the simplicity of the contrivance by

which all this heat is saved. It well deserves to be compared with

that by which the seasons are produced; and I must think that every

candid inquirer who will begin by divesting himself of all

unreasonable prejudice will agree with me in attributing them both TO

THE SAME AUTHOR....



"But I must take care not to tire my reader by pursuing these

speculations too far. If I have persisted in them, if I have dwelt on

them with peculiar satisfaction and complacency, it is because I think

them uncommonly interesting, and also because I conceived that they

might be of value in this age of refinement and scepticism.



"If, among barbarous nations, the fear of a God, and the practice of

religious duties, tend to soften savage dispositions, and to prepare

the mind for all those sweet enjoyments which result from peace,

order, industry, and friendly intercourse; a belief in the existence

of a Supreme Intelligence, who rules and governs the universe with

wisdom and goodness, is not less essential to the happiness of those

who, by cultivating their mental powers, HAVE LEARNED TO KNOW HOW

LITTLE CAN BE KNOWN."



Rumford, in connection with his experiments on the conducting power of

liquids, tried the effect of increasing the viscosity of water by the

addition of starch, and of impeding its movements by the introduction

of eider-down, on the rate of diffusion of heat through it. Hence he

explained the inequalities of temperature which may obtain in a mass

of thick soup--inequalities which had once caused him to burn his

mouth--and, applying the same principles to air, he at once turned his

conclusions to practical account in the matter of warm clothing.



After an attempt to determine, if possible, the weight of a definite

quantity of heat--an attempt in which very great precautions were

taken to exclude disturbing causes, while the balance employed was

capable of indicating one-millionth part of the weight of the body

weighed--Rumford, finding no sensible effect on the balance, concluded

that "if the weight of gold is neither augmented nor lessened by

one-millionth part, upon being heated from the point of freezing

water to that of a bright red heat, I think we may very safely

conclude that ALL ATTEMPTS TO DISCOVER ANY EFFECT OF HEAT UPON THE

APPARENT WEIGHTS OF BODIES WILL BE FRUITLESS." The theoretical

investigations of Principal Hicks, based on the vortex theory of

matter and the dynamical theory of heat, have recently led him to the

conclusion that the attraction of gravitation may depend to some

extent on temperature.



A series of very valuable experiments on the radiating powers of

different surfaces showed how that power varied with the nature of the

surface, and the effect of a coating of lamp-black in increasing the

radiating power of a body. In order to determine the effect of

radiation in the cooling of bodies, Rumford employed the thermoscope

referred to by Cuvier. The following passage is worthy of attention,

as the truth it expounds in the last thirteen words appears to have

been but very imperfectly recognized many years after it was

written:--



"All the heat which a hot body loses when it is exposed in the air to

cool is not given off to the air which comes into contact with it, but

... a large proportion of it escapes in rays, which do not heat the

transparent air through which they pass, but, like light, generate

heat only when and where they are stopped and absorbed."



Rumford then investigated the absorption of heat by different

surfaces, and established the law that good radiators are good

absorbers; and recommended that vessels in which water is to be heated

should be blackened on the outside. In speculating on the use of the

colouring matter in the skin of the negro, he shows his fondness for

experiment:--



"All I will venture to say on the subject is that, were I called to

inhabit a very hot country, nothing should prevent me from making the

experiment of blackening my skin, or at least, of wearing a black

shirt, in the shade, and especially at night, in order to find out if,

by those means, I could contrive to make myself more comfortable."



In his experiments on the conduction of heat, Rumford employed a

cylinder with one end immersed in boiling water and the other in

melting ice, and determined the temperature at different points in the

length of the cylinder. He found the difficulty which has recently

been forcibly pointed out by Sir Wm. Thomson, in the article "Heat,"

in the "Encyclopaedia Britannica," viz. that the circulation of the

water was not sufficiently rapid to keep the temperature of the layer

in contact with the metal the same as that of the rest of the water;

and he also called attention to the arbitrary character of

thermometer-scales, and recommended that more attention should be

given to the scale of the air thermometer. It was in his visit to

Edinburgh, in 1800, that, in company with some of the university

professors, the count conducted some experiments in the university

laboratory on the apparent radiation of cold. Rumford's views

respecting frigorific rays have not been generally accepted, and

Prevost's theory of exchanges completely explains the apparent

radiation of cold without supposing that cold is anything else than

the mere absence of heat.



We must pass over Rumford's papers on the use of steam as a vehicle of

heat, on new boilers and stoves for the purpose of economizing fuel,

and all the papers bearing on the nutritive value of different foods.

The calorimeter with which he determined the amount of heat generated

by the combustion, and the latent heat of evaporation, of various

bodies has been already alluded to. Of the four volumes of Rumford's

works published by the American Academy of Arts and Sciences, the

third is taken up entirely with descriptions of fireplaces and of

cooking utensils.



Before deciding on the best way to light the military workhouse at

Munich, Rumford made a series of experiments on the relative economy

of different methods, and for this purpose designed his well-known

shadow-photometer. In the final form of this instrument the shadows

were thrown on a plate of ground glass covered with paper, forming the

back of a small box, from which all extraneous light was excluded. Two

rods were placed in front of this screen, and the lights to be

compared were so situated that the shadow of one rod thrown by the

first light might be just in contact with that of the other rod thrown

by the second light. By introducing coloured glasses in front of the

lights, Rumford compared the illuminating powers of different sources

with respect to light of a particular colour. The complementary tints

exhibited by the shadows caused him to devise his theory of the

harmony of complementary colours. One result is worthy of mention: it

is a conclusion to which public attention has since been called in

connection with "duplex" burners. Rumford found that with wax tapers

the amount of light emitted per grain of wax consumed diminished with

the diminution of the consumption, so that a small taper gave out only

one-sixteenth as much light as an ordinary candle for the same

consumption of wax. He says:--



"This result can be easily explained if we admit the hypothesis which

supposes light to be analogous to sound.... The particles ... were so

rapidly cooled ... that they had hardly time to shine one instant

before they became too cold to be any longer visible."



An argand lamp, when compared with a lamp having a flat wick, gave

more light in the ratio of 100 to 85 for the same consumption of oil.



One of the latest investigations of Rumford was that bearing on the

effect of the width of the wheels on the draught of a carriage. To his

own carriage, weighing, with its passengers, nearly a ton, he fitted a

spring dynamometer by means of a set of pulleys attached to the

under-carriage and the splinter-bar. He used three sets of wheels,

respectively 1-3/4, 2-1/4, and 4 inches wide, and, introducing weights

into the carriage to make up for the difference in the weights of the

wheels, he found a very sensible diminution in the tractive force

required as the width of the wheels was increased, and in a truly

scientific spirit, despising the ridicule cast upon him, he persisted

in riding about Paris in a carriage with four-inch tyres.



But the piece of work by which Rumford will be best known to future

generations is that described in his paper entitled "An Inquiry

concerning the Source of the Heat which is excited by Friction." It

was while superintending the boring of cannon in the arsenal at Munich

that Rumford was struck with the enormous amount of heat generated by

the friction of the boring-bar against the metal. In order to

determine whether the heat had come from the chips of metal

themselves, he took a quantity of the abraded borings and an equal

weight of chips cut from the metal with a fine saw, and, heating them

to the temperature of boiling water, he immersed them in equal

quantities of water at 59-1/2 deg. Fahr. The change of temperature of the

water was the same in both cases, and Rumford found that there was no

change which he could discover in regard to its capacity for heat

produced in the metal by the action of the borer.



In order to prevent the honeycombing of the castings by the escaping

gas, the cannon were cast in a vertical position with the breech at

the bottom of the mould and a short cylinder projecting about two feet

beyond the muzzle of the gun, so that any imperfections in the casting

would appear in this projecting cylinder. It was on one of these

pieces of waste metal, while still attached to the gun, that Rumford

conducted his experiments. Having turned the cylinder, he cut away the

metal in front of the muzzle until the projecting piece was connected

with the gun by a narrow cylindrical neck, 2.2 inches in diameter and

3.8 inches long. The external diameter of the cylinder was 7.75

inches, and its length 9.8 inches, and it was bored to a depth of 7.2

inches, the diameter of the bore being 3.7 inches. The cannon was

mounted in the boring-lathe, and a blunt borer pressed by a screw

against the bottom of the bore with a force equal to the weight of

10,000 pounds. A small transverse hole was made in the cylinder near

its base for the introduction of a thermometer. The cylinder weighed

113.13 pounds, and, with the gun, was turned at the rate of thirty-two

revolutions per minute by horse-power. To prevent loss of heat, the

cylinder was covered with flannel. After thirty minutes' work, the

thermometer, when introduced into the cylinder, showed a temperature

of 130 deg. Fahr. The loss of heat during the experiment was estimated

from observations of the rate of cooling of the cylinder. The weight

of metal abraded was 837 grains, while the amount of heat produced was

sufficient to raise nearly five pounds of ice-cold water to the

boiling point.



To exclude the action of the air, the cylinder was closed by an

air-tight piston, but no change was produced in the result. As the air

had access to the metal where it was rubbed by the piston, and Rumford

thought this might possibly affect the result, a deal box was

constructed, with slits at each end closed by sliding shutters, and so

arranged that it could be placed with the boring bar passing through

one slit and the narrow neck connecting the cylinder with the gun

through the other slit, the sliding shutters, with the help of collars

of oiled leather, serving to make the box water-tight. The box was

then filled with water and the lid placed on. After turning for an

hour the temperature was raised from 60 deg. to 107 deg. Fahr., after an hour

and a half it was 142 deg. Fahr., at the end of two hours the temperature

was 178 deg. Fahr., at two hours and twenty minutes it was 200 deg. Fahr., and

at two hours and thirty minutes it ACTUALLY BOILED!



"It would be difficult to describe the surprise and astonishment

expressed in the countenances of the bystanders on seeing so large a

quantity of cold water heated and actually made to boil without any

fire.



"Though there was,



More

;