Celebrating 24 Years on the Web
Find science on or your birthday

Today in Science History - Quickie Quiz
Who said: “The conservation of natural resources is the fundamental problem. Unless we solve that problem it will avail us little to solve all others.”
more quiz questions >>
Thumbnail of Thomas Drummond (source)
Thomas Drummond
(10 Oct 1797 - 15 Apr 1840)

Scottish civil engineer who invented the Drummond light (similar to limelight) for night surveying, and attempted to adapt it for use in lighthouses.

Drummond's Inventions

Drummond Light and Lighthouse Experiments

from Memoir of Thomas Drummond (1867)

Thomas Drummond
Thomas Drummond

[p.81] ...Till the Spring of 1826, Mr Drummond remained invalided with his relations in Edinburgh. He was too weak for severe study; but he managed, notwithstanding, to effect a variety of improvements in his light apparatus, which he was bent on fitting for lighthouse use. In the spring he returned to London, where he was occupied during the summer and autumn in experiments for forming new measuring bars with which it was intended to measure the base at Lough Foyle. Late in the autumn he again took to the field. The station this year was Slieve Donard, in the County Down. Drummond joined the camp in October, and continued there till late in November. As in the previous year, the tempests were fearful, and must have grievously tried his already weakened condition. ...

[p.83] ...We now come to the operations of 1827 and 1828, and the inventions connected with the,. In these years, Mr Drummond was engaged in measuring the celebrated base of Lough Foyle—the most accurately measured base in the world, as Sir John Herschel assures me, except perhaps that measured by Maclear at the Cape by means of the same measuring apparatus. ...

[p.113] ...The anxiety and exposure attending the operations in 1828 had seriously affected his health—the second, if not the third time, that a severe illness had sprung out of his devotion to the service. He suffered much, as in the winter if 1825, from palpitation and sleeplessness. [p.114] He refers to this illness in a paper read before the Royal Society, June 17, 1830, “On the Illumination of Lighthouses.” The Trinity House Corporation had resolved, as early as 1826, to give his light a trial as soon as the apparatus should give a steady continuance of light, and be fit to be entrusted to ordinary attendants.” The survey of Ireland, however,” he says, “had just been commenced; and being employed on that service, I found it impossible to continue my experiments, in the first instance, from constant occupation and absence from London, and latterly, from & long and severe illness, the consequence of a very laborious and anxious duty in Ireland. During the last winter, however, I was again able to return to the subject.” The reference is to the measurement of the base, in the course of which he had suffered much from inclement weather, and from frequently standing in deep water (as in crossing the river), intent on the measurements, and regardless of himself.

This, as I have said, was the second, if not the third illness suffered in the service. Miss Drummond speaks of a severe illness, the date of which I am unable to fix. He occupied, she says, a hill-station in Ireland. The weather became tempestuous, and the station untenable; yet he held to his post at first from a sense of duty, but afterwards from inability to leave it. A chance visitor to the station, who happened to be a medical man, discovering his condition, hastened for assistance to the house of a landed proprietor in the neighbourhood. He described the camp hut as filled with water, and Drummond as certain to die if allowed to remain in it. The gentleman appealed to at once made for the hill, accompanied by his son. They found Drummond very ill, and had to carry him to the carriage, [p.115] where they rolled him in blankets which they had provided. Having taken him home, they nursed him with the greatest care and kindness, for the six weeks which passed before he was able to return to his mother's house. Miss Drummond's recollection is, that the name of these hospitable people was Mac Causland. She adds, “He was about a fortnight with us before he was able to go out just a little. I remember the Survey people wanted to stop his pay. He wrote them a thundering letter. ‘Was there ever anything equal to this?’ he said; ‘they throwaway thousands of pounds, and would rob me when I am become disabled in their service.’” He heard no more of the threat to “suspend payments.” It seems impossible that this account can refer to the illness which followed the sojourn on Slieve Snaght. Larcom thinks the time must have been the close of the first season at the Base.

He arrived in London late in the autumn of 1829, to prosecute his design of fitting the lime-light for lighthouse use. He had been engaged in improving the apparatus for this purpose in the spring of 1826, and may then have got it nearly into shape; he was certainly ready to bring it into use very soon after his return to town. Before the end of the year he was busy with experiments instituted by order of the Trinity House, for ascertaining the relative merits of the different methods of illumination in lighthouses. Some of these were carried on at the Trinity House; others at a small lighthouse at Purfleet, which had been placed at his disposal by the Corporation. They were conducted under the direction of the Committee for the Management of the Lighthouses, and they fairly established the superiority, at least in brilliancy; of the Drummond Light over all others.

[p.116] The original light apparatus had been designed for the Survey. Portability, rather than economy, had been studied in its construction. The ball of lime—from which when intensely ignited the light was derived—was heated by means of a stream of oxygen directed through a flame of spirit of wine. This source of heat was expensive, and, in considering the changes now to be made, economy was a primary object. For the alcohol Drummond substituted hydrogen gas, which proved not only much more economical, but productive of a considerable increase of brilliancy in the light.

The new apparatus was exceedingly ingenious. The oxygen and hydrogen gases, proceeding from separate gasometers, arrive at a small chamber, where they are made to mix. Into this chamber the oxygen gas is projected horizontally through a series of very small apertures, the hydrogen gas rising into it vertically through a series of similar apertures. From this the united gases pass through two or three pieces of wire gauze, and, being thoroughly mixed, issue through two jets against the lime ball in the focus of the reflector. To prevent the wasting of the ball opposite the two jets, and at the same time to diffuse the heat more equally, the ball is made by the apparatus to revolve once in a minute. Notwithstanding this movement, the heat cuts a deep grove in the ball, and it becomes necessary to replace it by a new one every three-quarters of an hour. As it would be unsafe in a lighthouse to intrust the replacing of the ball to an attendant, the apparatus is so contrived that it effects the replacement itself. The number of balls required to maintain the light for any time are placed on a. wire passing through the focus of the reflector; the ball in the focus drops the moment it is sufficiently worn, and its place [p.117] is instantly taken by another—the next above it on the wire—which two minutes before has fallen into a position to be gradually heated for doing duty in the focus.1

From a letter dated January 16, 1830, written to his sister, it appears that the Duke of Clarence, who a few months later became King William IV., had been expected to witness the experiments in his character of Master of the Trinity Corporation; and that an experiment which had been made with thc lime-light, before the apparatus had been brought into perfect working order, had resulted in an explosion. Miss Drummond had cautioned her brother not to enter upon the experiments till he had completed his preparations.

London, January 16, 1830.

My Dear Eliza,—A week, more than a week, has passed since I ought, and since I intended, to have answered your kind, kind letter; but every day and every evening has brought such constant occupation that I positively have not had time.

“The consequence, no doubt, has been many conjectures, and much exercise to my dear mother, if the bell rang about post-time. Now, what have been your conjectures? Another explosion, perhaps, and the heir-presumptive, along with all my beautiful apparatus, sent to the upper, or perhaps the under regions; or everything gone off well, and the Duke extremely [p.118] delighted, expressed himself highly gratified, and intended conferring upon me some signal mark of his royal approbation! Well, to keep you in suspense no longer. The Duke was not present; he was unwell, and unable to leave his house. We were all prepared, for the messenger did not arrive till the last moment. The next Board day, when he is expected, is the 5th February. Meanwhile we proceed with the experiments, and it is with them that I have been so much engaged this week. But this is Saturday evening, an evening of repose and enjoyment, and I have taken advantage of it to discharge my debt to you. I was grieved to hear of more colds and plaisters, and I fear much that this fierce weather does not agree with you. . . . Do you ride? How is the pony? Has John recovered, and has he been laying down the law? I think you might manage among you to write a little oftener. There are some long gaps in our correspondence, and some long intervals during which I hear nothing of you. . . . Almost all my acquaintances have been ill more or less. I have great reason to be thankful that I have kept so well; indeed, notwithstanding all my work, I am in rude health, sleep but one sleep, and no palpitation. All the advice you gave me in your letter I acknowledge to be excellent, yet the exhibition was unavoidable, and so was the explosion. But I think they have got over it; if not, I will tell them the first time I have an opportunity of making a speech, that if I had been making an experiment before men unacquainted with the peculiar nature of such experiments, I should have declined proceeding under such circumstances; but before enlightened and intelligent men, whose indulgence and partiality I had more than once experienced, I could have no hesitation in trying even a first experiment, deeming it the best compliment I could pay them to show them the apparatus under the most disadvantageous circumstances. . . . My best and kindest love to you all at home. Adieu, my dearest Eliza, and believe me your ever affectionate brother, T. Drummond.”


The Duke of Clarence was present, and highly gratified, when the lights were exhibited at the Trinity House on the 5th of March; after the exhibition he [p.119] presided at a dinner of the Corporation, to which Drummond went as a guest. By the month of May 1830 the scene of the experiments was transferred to the lighthouse at Purfleet. The light was making a sensation again, many of the most distinguished men in London going to witness its brilliant effects. Though Drummond did not oppose the experiments for testing the efficacy of the light at a distance, as that might have been impolitic, his view of them, expressed to his mother, was, that they were “mere trifling, and waste of time.” They were spreading his reputation, however, and every day bringing him new friends. By this time, six of his lights had been ordered by the East India Company, at the cost of L100 apiece. He was astonished at, but rather regretted, the Company's liberality, considering the hands into which the lights would fall. “I am busy,” he says, “preparing an account of our operations in Ireland, to be delivered as a lecture on Friday at the Royal Institution.”2 Friday was also to see the last of the experiments on the lights. “I will then present a report to the Trinity House, and they will decide what further steps should be taken. I am writing a paper on the experiments for the Royal Society.”3

This paper has been already referred to. It opens with a rapid history of methods of illuminating lighthouses, and account of those in use in the best lighthouses of Great Britain and France; a description, accompanied by illustrative plates, of the new apparatus [p.120] for exhibiting the Drummond light is next given, and is followed by a summary of the results of the Trinity House and Purfleet experiments.

The first set of the experiments were on the illuminating powers of the different lights, independently of the lenses or reflectors with which they are generally used. In these the method of shadows, and that of equally illuminated surfaces, both dependent on the same principle, but requiring different instruments, were employed. The standard used was an Argand lamp, 7/8 inch in diameter, supplied with the finest spermaceti oil, and capable of supporting a flame 1¾ inch in height. It was found that the light emitted by the French lamp, a large Argand, with four concentric wicks, was equal to ten standards; while that emitted by a lime-ball only 3/8 of an inch in diameter,. heated by two jets, was equal to thirteen standards. The next set of experiments respected the intensity or intrinsic brightness of the lights, the property on which their utility in lighthouses more immediately depends. The French lamp was found to be four times, while the lime-light was 264 times as intense as the standard! “These results,” says Mr Drummond, "were obtained by screening the lights, and then placing equal apertures opposite each, changing the apertures, and taking the mean to destroy the effect of any inaccuracy in size. The intensity of the lime-ball being, therefore, 264 times that of the Argand lamp, a single reflector, illuminated by the former, will be equal to 264 reflectors illuminated by the latter; but the divergence of the reflected light, depending on the size of the luminous body in the focus, will he smaller with the ball than with the lamp, in the proportion of about 3 to 8; hence, in such a lighthouse as that of Beachy Head, 8 reflectors may be [p.121] substituted for 30, and yet an effect would be produced 26 times greater than that of the present light, the most perfect of its kind in this country.”

By similar experiments, it was found that the French lens, a compound one, built up of separate pieces, on a principle first suggested by Sir David Brewster, was equal to 10·4 reflectors, taking into account the effect of the additional lenses and reflectors that ought to accompany it; and that the effect of a single reflector with a lime-ball would be equal to 25 times that of the French lens, accompanied by those additional lenses and reflectors.

“Such appear to be the singular and important results,” says Mr Drummond, “of our late experiments at the Trinity House. Made with every precaution by different individuals with different instruments, and unbiassed by the knowledge of each other's results, I see no reason to doubt their accuracy; and the comparative appearances of the different lights, when exhibited at a distance of ten miles, though not admitting of being reduced to numbers, confirm the striking superiority of this method of illumination."

The comparative appearances of the lights, as seen at a distance, are described in a letter, addressed to Mr Drummond by Captain Basil Hall. The lights were exhibited from the temporary lighthouse erected at Purfleet, and were observed from the Trinity Wharf, Blackwall, at a distance in a straight line of 10¼ miles. Drummond being engaged at Purfleet, could not himself judge of the effect. But among the observers were Sir George Cockburn and Mr Barrow from the Admiralty, accompanied by several naval officers of high standing; the Lord-Advocate of Scotland, Sir Thomas Brisbane, Colonel Colby, Captain Beaufort, hydrographer [p.122] to the Admiralty, and several others eminent for their professional and scientific attainments. Captain Hall assured Mr Drummond that he had endeavoured “to frame his account of what passed in strict conformity with the general sentiments of the party, and neither to exaggerate nor underrate any of the results.”

“4 St James’ Place, June 1, 1830.

My Dear Sir,—You wished me to take particular notice of last night's experiments with the different kinds of lights exhibited at Purfleet, and observed at the Trinity Wharf, Blackwall; but I have little to add to what I told you respecting those on the evening of the 25th instant; indeed, it is not within the compass of language to describe accurately the details of such experiments, for it is by ocular evidence alone that their merits can be understood.

“Essentially, the experiments of last evening were the same as those of the 25th, and their effects likewise. The degrees of darkness in the evenings, however, were so different, that some particular results were not the same. The moon last night being nine or ten days older, lighted up the clouds so much, that even when the moon herself was hid, there was light enough to overpower any shed upon the spot where we stood by your distant illumination; whereas, on the 25th, when the night was much darker, the light cast from the temporary lighthouse at Purfleet, in which your apparatus was fixed, was so great, that a distinct shadow was thrown upon the wall by any object interposed. Not the slightest trace of any such shadow, however, could be perceived when your light was extinguished, and any of the other lights were exposed in its place.

“In like manner, on the evening of the 25th, it was remarked by all the party at the Trinity Wharf, that, in whatever direction your light was turned, an immense coma. or tail of rays, similar to that produced by a beam of sunlight in a dusty room, but extending several miles in length, was seen to stream off from the spot where we knew the light to be placed, [p.123] although, owing to the reflector being turned too much on one side, the light itself was not visible.

“Now, last night there was none of this singular appearance visible; but whether this was caused by the presence of the moonlight, or by the absence of the haze and drizzling rain which fell during the evening of the 25th. I cannot say. I had hoped that the appearance alluded to was to prove a constant accompaniment to your light. in which case it might, perhaps, have been turned to account for the purposes of lighthouses. If in hazy or foggy weather this curious effect of reflected light from the atmosphere be constant, it may help to point out the position of lighthouses, even when the distance of the observer is so great that the curvature of the earth shall render it impossible for him to see the light itself.

“The following experiments, tried last night, were the same as those of the 25th, and certainly no comparative trials could be more fairly arranged:—

Exp. I. The first light exposed was the single Argand burner, with a reflector. This was quite distinctly seen, and all the party admitted it be a good light. After several minutes, this was put out.

Exp. II. The seven Argand burners were next shown, each in its reflector; and this was manifestly superior to the first; but how much so I cannot say—perhaps four times as conspicuous. Both these lights had an obvious tinge of brown or orange.

Exp. III. The third light which was exposed (on the seven Argands being put out), was that behind the French lens; and I think it was generally admitted by the party present that this light was whiter and more intense than that from the seven Argands, though the size appeared very much the same.

Exp. IV. The fourth light was that which you have devised, and which, instead of the clumsy word ‘lime,’ ought to bear the name of its discoverer. The Drummond light, then, the instant it was uncovered, elicited a sort of shout of admiration from the whole party, as being something much more brilliant than we had looked for. The light was not only more [p.124] vivid and conspicuous, but was peculiarly remarkable from its exquisite whiteness. Indeed, there seems no great presumption in comparing its splendour to that of the sun; for I am not sure that the eye would be able to look at a disc of such light, if its diameter were made to subtend half a degree.

“The next series of experiments was the most interesting and decisive of all. Each of the lights above enumerated, viz., the single Argand burner, the seven Argands, and the French lens, were exposed, one at a time, in company with your light, in order to try their relative brilliancy.

First comparative Experiment.—The single Argand burner was first exposed to this comparative ordeal, and nothing could be more pitiable than the figure it cut. Many of the party could not see the Argand light at all; while others could just detect it ‘away in a corner,’ as some one described it. It was also of a dusky orange tinge, while your light was of the most intense whiteness.4

Second comparative Experiment.—The seven Argand burners were now substituted in place of the single light. All the party could now see both lights, but the superiority was not much less obvious. I really can not affix a proportion either as to size or brilliancy; but I should not hesitate to say that your light was at least six or eight times as conspicuous; while in brilliancy, or purity, or intensity of light (for I know not precisely what word to use to describe the extreme whiteness), the superiority was even more remarkable. All this which I have been describing was expressed, and appeared to be quite as strongly felt, by the rest of the company, to the number, I should suppose, of five-and-twenty or thirty persons, who were all closely on the watch.

Third comparative Experiment.—The next comparative trial was between the French lens and your light. The superiority here was equally undeniable, though the difference in the degree of whiteness was not so remarkable. The French [p.125] light, however, is so nearly similar to that from the seven Argands, that the comparison of each of them with your light gave nearly the same results, and all equally satisfactory on the score of your discovery.

Final Experiment.—The flashes with which the experiments concluded were very striking, and might, I think, be turned to great account in rendering lighthouses distinct from one another. The revolutions were not effective, and, as I said before, there was no appearance last night of those enormous comets' tails which swept the horizon on the night of the 25th, to the wonder of all who beheld them: neither could there be detected the slightest trace of any shadow from the light thrown towards us; and I suspect none will ever be seen, when the moon, whether the night be clouded or not, is of so great a magnitude.

“Such is the best account I can give of what we witnessed; and I need only add, that there seemed to be amongst the company but one opinion of the immense superiority of your light over all the others brought into comparison with it.—I am, &c. Basil Hall.”


The superior brilliancy of the light being thus established, the only point for farther inquiry was the expense of its production. The result of Mr Drummond's inquiries on this point are set forth in his paper, and are unfavourable to his light. “It may, however, in this, as in every similar instance,” he observes, “be expected that, after a little experience, a considerable reduction in the cost would be effected.”

"This is a new source of artificial light, differing from every other at present in use, and the materials by which it is produced are among the most abundant products of nature; but never having yet been applied on a great scale to any practical purpose, it has not hitherto been an object to obtain them in a separate state at a small expense. . . . Meanwhile, however, the case in question may perhaps be regarded as one where expense ought not to be a primary object of consideration. On all ordinary occasions, the preference of one mode of illumination [p.126] nation to another is a question of convenience, luxury, or economy; but in this it assumed a more important character, for it involves to a great extent the preservation of life and property. . . . . The advantage of the light being fully recognised, attention may now be exclusively directed to remove some of those minor obstacles that might render its use in lighthouses objectionable; and I have great pleasure in adding, that the Trinity Corporation are desirous that every facility in their power should be afforded with a view to effect this object, and that a series of preliminary experiments is accordingly to be carried out at their expense.”

It was but for a short time that Mr Drummond was free to prosecute such inquiries. He was engaged in them up to the spring of 1831. In a letter to his mother, dated February 22, 1831, he writes: “Truly this same light gives no small trouble. . . . In the last paper which I sent to the Commissioners, I stated that the French light equals, if it does not surpass, the best of the lights in our lighthouses in splendour, while it is superior to them in economy and facility of management. This Stevenson either denies, or has hitherto been negligent in ascertaining. . . . The experiments at Inchkeith have been ordered by the Commissioners [of the Northern Lights], with a view to judge of the point themselves, and not trust to Stevenson's opinion. It is a question between the present method and the French light, not between mine and either. Their relative values have been ascertained by the Trinity House and Blackwall experiments, in a way which admits of no doubt. To recommence similar experiments would be mere trifling. There are obstacles in my way of a different kind, relating to the manufacture of the gas, management, &c., which I am now endeavouring to remove. With respect to brilliancy there can be no doubt." By the middle [p.127] of the year, however, his political employment commenced; and though he never lost sight of the subject, he was never able again to recur to it. “This abstraction of Mr Drummond's attention,” says General Larcom, “at the moment when he was nearest to success, must, so far as the light is concerned, be considered matter of regret: with its projector it has dropped; but if it be practicable, ingenuity will, doubtless, sooner or later, be directed to render it available, and the Drummond light may yet cheer the homebound mariner from the Great Skellig or the Tuakar."5....

1. This description is an abridgment from Mr Drummond's paper in the “Philosophical Transactions.” There is an alternative contrivance for maintaining the constancy of the light in certain cases. Whenever the light is required to be diffused equally around, the renewal of the lime may be effected still more easily, by using a cylinder instead of a ball, which being gradually raised while revolving, brings fresh portions in succession opposite the jets. In a reflector a cylinder occasions partial shadows at the top and bottom; still, however, the simplicity and certainty with which it may be renewed, will probably entitle it to a preference even in this case.” — Phil.Trans. 1830, p. 388.
2. Letter to Mrs Drummond, 9th May 1830.
3. Drummond was elected a Fellow of the Royal Astronomical Society, May 14, 1830. He was proposed in March of the same year. In a letter belonging to that month, he says, “I am doing all I can to render myself an efficient member of the Astronomical.”
4. “To many the rays from the brighter light appeared, when seen with the naked eye, to extend across and envelope the fainter light, though the perpendicular distance between them was twenty-five yards.”
5. For some time the Drummond light has gone out of public notice. The interest and the expectations it excited at one time may be gathered from a question put to Mr Drummond when under examination as a witness before the Select Committee on Lighthouses in April 1834. “The Committee would like very much to have it on their minutes what circumstances gave rise to this very great and important discovery, which is likely to be of such infinite use to the world at large?” In an article in the “Edinburgh Review” for April 1835, reviewing the Report of this Committee, a suggestion of Sir David Brewster's that the Drummond light should be employed as a separate instrument in every lighthouse for occasional use, is considered and adopted. The occasional light was proposed to be used only in hazy weather, when other lights are either altogether obscured, or lose their characteristic appearances.” The general system of illumination by oil or gas lamps and lenses is adequate, in ordinary weather, to every want of the navigator; and nothing could be more irrational than to introduce the lime-ball light into lighthouses as a general mode of illumination—unless it could be done as cheaply, as safely, and as effectually as the present improved system with oil or gas lights. ... The lime-ball light holds out to us an admirable resource in seasons of occasional danger; but we cannot approve of the idea of making an unnecessary glare upon our coasts, with the inseparable accompaniments of unnecessary expense and unneccesary danger.” The inadequacy of the ordinary lights {or other than ordinary weather, i.e., for all occassions when their aid is most wanted, is here confessed. On the other hand, that greater expense and danger are inseparable from the use of the Drummond light is assumed, but is by no means certain. Had Mr Drummond been free for a little longer to follow up the subject, it is not improbable that his ingenuity would have enabled him to overcome these objections, and that ere now his light would have superseded every other for lighthouse purposes. The following recommendation of the Committee on Lighthouses seems not to have been attended to. They say— “Captain Drummond stated to the Committee all the objections to the present use of hie light in lighthouses; but your Committee are so strongly impressed with its importance, and with the merits and ability of Captain Drummond, that they recommend that means should be adopted without delay for prosecuting still farther the experiments recommended by him, and under his direction if possible; or, if he cannot superintend them, then under some fit person.”

Frontispiece and extracts from John Ferguson M'Lennan, Memoir of Thomas Drummond (1867), part of Chapter VIII, pages 81 & 83 and part of Chapter IX, pages 113-127. (source)

See also:
  • 10 Oct - short biography, births, deaths and events on date of Drummond's birth.
  • Thomas Drummond Inventions - from Memoir of Thomas Drummond (1867).
  • 9 Nov - brief description for first practical use of limelight on 9 Nov 1826.
  • Thomas Drummond: Under-secretary in Ireland, 1835-40; Life and Letters, by R. Barry O'Brien. - book suggestion.

Nature bears long with those who wrong her. She is patient under abuse. But when abuse has gone too far, when the time of reckoning finally comes, she is equally slow to be appeased and to turn away her wrath. (1882) -- Nathaniel Egleston, who was writing then about deforestation, but speaks equally well about the danger of climate change today.
Carl Sagan Thumbnail Carl Sagan: In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. (1987) ...(more by Sagan)

Albert Einstein: I used to wonder how it comes about that the electron is negative. Negative-positive—these are perfectly symmetric in physics. There is no reason whatever to prefer one to the other. Then why is the electron negative? I thought about this for a long time and at last all I could think was “It won the fight!” ...(more by Einstein)

Richard Feynman: It is the facts that matter, not the proofs. Physics can progress without the proofs, but we can't go on without the facts ... if the facts are right, then the proofs are a matter of playing around with the algebra correctly. ...(more by Feynman)
Quotations by:Albert EinsteinIsaac NewtonLord KelvinCharles DarwinSrinivasa RamanujanCarl SaganFlorence NightingaleThomas EdisonAristotleMarie CurieBenjamin FranklinWinston ChurchillGalileo GalileiSigmund FreudRobert BunsenLouis PasteurTheodore RooseveltAbraham LincolnRonald ReaganLeonardo DaVinciMichio KakuKarl PopperJohann GoetheRobert OppenheimerCharles Kettering  ... (more people)

Quotations about:Atomic  BombBiologyChemistryDeforestationEngineeringAnatomyAstronomyBacteriaBiochemistryBotanyConservationDinosaurEnvironmentFractalGeneticsGeologyHistory of ScienceInventionJupiterKnowledgeLoveMathematicsMeasurementMedicineNatural ResourceOrganic ChemistryPhysicsPhysicianQuantum TheoryResearchScience and ArtTeacherTechnologyUniverseVolcanoVirusWind PowerWomen ScientistsX-RaysYouthZoology  ... (more topics)

Thank you for sharing.
- 100 -
Sophie Germain
Gertrude Elion
Ernest Rutherford
James Chadwick
Marcel Proust
William Harvey
Johann Goethe
John Keynes
Carl Gauss
Paul Feyerabend
- 90 -
Antoine Lavoisier
Lise Meitner
Charles Babbage
Ibn Khaldun
Ralph Emerson
Robert Bunsen
Frederick Banting
Andre Ampere
Winston Churchill
- 80 -
John Locke
Bronislaw Malinowski
Thomas Huxley
Alessandro Volta
Erwin Schrodinger
Wilhelm Roentgen
Louis Pasteur
Bertrand Russell
Jean Lamarck
- 70 -
Samuel Morse
John Wheeler
Nicolaus Copernicus
Robert Fulton
Pierre Laplace
Humphry Davy
Thomas Edison
Lord Kelvin
Theodore Roosevelt
Carolus Linnaeus
- 60 -
Francis Galton
Linus Pauling
Immanuel Kant
Martin Fischer
Robert Boyle
Karl Popper
Paul Dirac
James Watson
William Shakespeare
- 50 -
Stephen Hawking
Niels Bohr
Nikola Tesla
Rachel Carson
Max Planck
Henry Adams
Richard Dawkins
Werner Heisenberg
Alfred Wegener
John Dalton
- 40 -
Pierre Fermat
Edward Wilson
Johannes Kepler
Gustave Eiffel
Giordano Bruno
JJ Thomson
Thomas Kuhn
Leonardo DaVinci
David Hume
- 30 -
Andreas Vesalius
Rudolf Virchow
Richard Feynman
James Hutton
Alexander Fleming
Emile Durkheim
Benjamin Franklin
Robert Oppenheimer
Robert Hooke
Charles Kettering
- 20 -
Carl Sagan
James Maxwell
Marie Curie
Rene Descartes
Francis Crick
Michael Faraday
Srinivasa Ramanujan
Francis Bacon
Galileo Galilei
- 10 -
John Watson
Rosalind Franklin
Michio Kaku
Isaac Asimov
Charles Darwin
Sigmund Freud
Albert Einstein
Florence Nightingale
Isaac Newton

by Ian Ellis
who invites your feedback
Thank you for sharing.
Today in Science History
Sign up for Newsletter
with quiz, quotes and more.