Dictionary of National Biography, 1885-1900/Davy, Humphry

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1305156Dictionary of National Biography, 1885-1900, Volume 14 — Davy, Humphry1888Robert Hunt

DAVY, Sir HUMPHRY (1778–1829), natural philosopher, was born at Penzance in Cornwall on 17 Dec. 1778. The parish register of Madron (the parish church) records 'Humphrey Davy, son of Robert Davy, baptized at Penzance, January 22nd, 1779. Robert Robert Davy was a wood-carver at Penzance, who pursued his art rather for amusement than profit. As the representative of an old family (monuments to his ancestors in Ludgvan Church date as far back as 1635) he became possessor of a modest patrimony. His wife, Grace Millett, came of an old but no longer wealthy family. Her parents died within a few hours of each other from malignant fever, when Grace and her two sisters were adopted by John Tonkin, an eminent surgeon in Penzance. Robert Davy and his wife became the parents of five children—two boys, Humphry, the eldest, and John, who is separately noticed, and three girls. In Davy's childhood the family removed from Penzance to Varfell, their family estate in Ludgvan. Davy's boyhood was spent partly with his parents and partly with Tonkin, who plaoeahim at a preparatory school kept by a Mr. Bushell, who was so much struck with the boy's progress that he persuaded the father to send him to a better school. He was at an early age placed at the Penzance grammar school, then under the car of the Rev. J.C. Coryton. Numerous anecdotes show that he was a precocious boy. He possessed a remarkable memory, and was singularly rapid in acquiring knowledge of books. He He was especially attracted by the 'Pilgrim's Progress,' and he delighted in reading history. When but eight years of age he would collect a number of boys, and standing on a cart in the market-place address them on the subject of his latest reading. He delighted in the folklore of this remote district, and became, as he himself tells us, a 'tale-teller.' The 'applause of my companions,' he says, 'was my recompense for punishments incurred for being idle.' These conditions developed a love of poetry and the composition of verses and ballads. At the same time he acquired a taste for experimental science. This was mainly due to a member of the Society of Friends named Robert Dunkin, a saddler; a man of original mind and of the most varied acquirements. Dunkin constructed for himself an electrical machine, voltaic piles, and Leyden jars, and made models illustrative of the principles of mechanics. By the aid if these appliancs he instructed Davy in the rudiments of science. As professor at the Royal Institution, Davy went in 1793 to Truro, and finished his education under the Rev. Dr. Cardew, who, in a letter to Davies Gilbert, says: 'I cound not discern the faculties by which he was afterwards so much distingiuished.' Davy says himself: 'I consider it fortunate I was left much to myself as a child, and put upon no particular plan of study … What I am I made myself.'

After the death of Davy's father in 1794, Tonkin apprenticed him to John Bingham Borlase, a surgeon in large practice at Penzance. His indenture is dated 10 Feb. 1795. In the apothecary's dispensary he became a chemist. A garret in Tonkin's house was the scene of his earliest chemical operations. His friends would often say: 'This boy Humphry is incorrigible. He will blow us all into the air,' and his eldest sister complained of the ravages made on her dresses by corrosive substances.

Much has been said of Davy as a poet, and Paris somewhat hastily says that his verses 'bear the stamp of lofty genius.' His first production preserved bears the date of 1795. It is entitled 'The Sons of Genius,' and is marked by the usual immaturity of youth. The poems, produced in the following years, eapecially those 'On the Mount's Bay' and 'St. Michael's Mount,' are pleasingly descriptive verses, showing sensibility, but no true poetic imagination. Davy soon abandoned poetry for science. While writing verses at the age of seventeen in honour of his first love, he was eagerly discussing with his quaker friend the question of the materiality of heat. Dunkin once remarked : 'I tell thee what, Humphry, thou art the most quibbling hand at a dispute I ever met with in my life.' One winter day he took Dunkin to Larigan river, to show him that the rubbing of two plates of ice together developed sufficient heat by motion to melt them, and that the motion being suspended the pieces were united by regelation. This was, in a rude form, the elementary experiment of an analogous one exhibited in later years by Davy in the lecture-room of the Royal Institution, which excited considerable attention.

Davies Giddy, afterwards Gilbert [q. v.], accidentally saw Davy in Penzance. The lad was carelessly swinging on the half-gate of Dr. Dorlase's house. Gilbert was interested by the lad's talk, offered him the use of his library, and invited him to his house at Tredrea. This led to an introduction to Dr. Edwards, who then resided at Hayle Copper House, and was also chemical lecturer in the school of St. Bartholomew's Hospital. Dr. Edwards permitted Davy to use the apparatus in his laboratory, and appears to have directed his attention to the floodgates of the port of Hayle, which were rapidly decaying from the contact of copper and iron under the influence of sea-water. This galvanic action was not then understood, hut the phenomenon prepared the mind of Davy for his experiments on the copper shrathing of ships in later days. Gregory Watt, the son of James Watt, visited Penzance for his health's sake, and lodging at Mrs. Davy's house became a friend of her son and gave him instructions in chemistry. Davy also formed a useful acquaintance with the Wedgwoods, who spent a winter at Penzance.

Dr. Beddoes and Professor Hailstone were engaged in a geological controversy upon the rival merits of the Plutonian and the Neptunist hypotheses. They travelled together to examine the Cornish coast accompanied by Davies Gilbert, and thus made Davy's acquaintance. Beddoes, who had recently established at Bristol a 'Pneumatic Institution,' required an assistant to superintend the laboratory. (Gilbert recommended Davy for the post, and Gregory Watt placed (in April 1798) in the hands of Beddoes the 'Young man's Researches on Heat and Light,' which were subsequently published by him in the first volume of 'West-Country Contributions.' Prolonged negotiations were carried on, mainly by Gilbert. Mrs. Davy and Borlase consented to Davy's departure, but Tonkin desired to fix him in his native town as a surgeon, and actually altered his will when he found that Davy insisted on going to Dr. Beddoes. On 2 Oct. 1798 Davy joined the 'Pneumatic Institution' at Bristol. This institution was established for the purpose of investigating the medical powers of factitious airs and gases, and to Davy was committed the superintendence of the various experiments. The arrangement concluded between Dr. Beddoes and Davy was a liberal one, and enabled Davy to give up all claims upon his paternal property in favour of his mother. He did not intend to abandon the profession of medicine, being still determined to study and graduate at Edinburgh. He, however, soon found his whole energies absorbed in the labours of the laboratory. During his residence at Bristol Dayy formed the acquaintance of the Earl of Durham, who became a resident for his health in the Pneumatic Institution, and of Coleridge and Southey. In December 1799 he visited London for the first time, and his circle of friends was there much extended.

In this year the first volume of the 'West-Country Collections' was issued. Half of the volume consisted of Davy's essays 'On Heat, Light, and the Combinations of Light,' ' On Phos-oxygen and its Combinations,' and on the 'Theory of Respiration.' On 22 Feb. 1799 Davy, writing to Davies Gilbert, says: 'I am now as much convinced of the non-existence of caloric as I am of the existence of light.' In another letter written to Davies Gilbert on 10 April he informs him : 'I made a discovery yesterday which proves how necessary it is to repeat experiments. The gaseous oxide of azote (the laughing gas) is perfectly respirable when pure. It is never deleterious but when it contains nitrous gas. I have found a mode of making it pure.' He then says that he breathed sixteen quarts of it for nearly seven minutes, and that it 'absolutely intoxicated me.' During this year Davy published his 'Researches, Chemical and Philosophical, chiefly concerning Nitrous Oxide and its Respiration.' In after years Davy regretted that he had ever published these immature hypotheses, which he himself subsequently designates as 'the dreams of misemployed genius which the light of experiment and observation has never conducted to truth.'

In 1800 Davy informed Davies Gilbert that he had been 'repeating the galvanic experiments with success' in the intervals of the experiments on the gases, which 'almost incessantly occupied him from January to April.' In these experiments Davy ran considerable risks. The respiration of nitrous oxide led, by its union with common air in the mouth to the formation of nitrous acid, which severely injured the mucous membrane, and in his attempt to breathe carburetted hydrogen gas he 'seemed sinking into annihilation.' On being removed into the open air he faintly articulated, 'I do not think I shall die,' but some hours elapsed before the painful symptoms ceased.

Davy's 'Researches,' which were full of striking and novel facts, and rich in chemical discoveries, soon attracted the attention of the scientific world, and Davy now made his grand move in life. In 1799 Count Rumford had proposed the establishment in London of an 'Institution for Diffusing Knowledge,' i.e. the Royal Institution. The house in Albemarle Street was bought in April 1799. Rumford became secretary to the institution, and Dr. Garnett was the first lecturer. Garnett was forced to resign from ill-health in 1801. Rumford had already been empowered to treat with Davy. Personal interviews followed, and on 15 July 1801 it was resolved by the managers 'that 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 100l. per annum.'

Rumford held out to Davy the prospect of his becoming in two or three years professor of chemistry in the Institution with a salary of 800l. per annum, and agreed that Davy should have every facility for pursuing his private philosophical investigations.

On 11 March 1801 Davy arrived at the Royal Institution. He gave three courses of lectures in the spring of that year. His first course, consisting of five lectures, was 'On the New Branch of Philosophy,' embracing the history of galvanism and the discoveries made by himself and others. This course was followed by another on 'Pneumatic Chemistry,' and after the concluding lecture on 20 June, he administered the nitrous oxide (laughing gas) to several gentlemen present. Another course on 'Galvanism' was delivered in the fore part of the day, which was attended by men of science and numbers of people of rank and fashion. On 21 Jan. 1802 Davy delivered the introductory lecture of the session to his course on 'Chemistry' in the theatre of the Royal Institution upon benefits to be derived from the various branches of science. He also gave an evening course on 'Chemistry applied to the Arts.' On 21 May it was resolved 'that Mr. Humphry Davy be for the future styled professor of chemistry at the Royal Institution.' In April Davy joined Dr. Young in editing the eighth number of the 'Journal of the Royal Institution.' In one of these he gave his 'account of a method of copying paintings upon glass, and of making profiles by the agency of light upon nitrate of silver, invented by J. Wedgwood, Esq.' Davy's first communication to the Royal Society was an 'Account of some Galvanic Combinations.' It was read on 18 June 1801. On 24 Feb. 1803 he read before the Royal Society his first paper on 'Astringent Vegetables and on their Operation in Tanning.' He was proposed a fellow on 21 April 1803 and elected on 17 Nov. On 7 July he was elected an honorary member of the Dublin Society. Davy had at this time arrived at his period of most healthful popularity. Dr. Paris says of him: 'The enthusiastic admiration which his lectures obtained is at this period scarcely to be imagined. Men of the first rank and talent, the literary and the scientific, the practical, the theoretical, blue stockings, and women of fashion, the old, the young, all crowded, eagerly crowded the lecture-room.' Coleridge on 17 Feb. 1803 expressed his pleasure at Davy's progress, and said that he hoped 'more proudly of Davy than of any other man,' but afterwards noticed the danger of dissipation and flattery, 'two serpents at the cradle of his genius.' On 10 May Davy's first lecture was given before the board of agriculture, and five others on succeeding Tuesdays and Fridays. A prologue, written in two hours, for Tobin's comedy of the 'Honeymoon,' produced at Drury Lane on 30 Jan. 1805, showed that his poetical tendencies were not entirely suppressed. The success of his lectures was followed by the glory of original discoveries. In 1806 he presented to the Royal Institution a collection of minerals which Mr. Hatchett pronounced to have an aggregate value exceeding one hundred guineas, and the managers of the institution, on the representation of that mineralogist, resolved 'that the sum of one hundred pounds be entrusted to Mr. Davy to purchase minerals.' On 4 Feb. in this year Davy was appointed director of the laboratory, his annual income being raised to 400l. a year. On 16 May 1800 Davy communicated a paper to the Royal Society on the use of boracic acid in analysing stones, and for this and his previous papers the council of the Royal Society adjudged to him their Copley medal. He was elected secretary to that society on 22 Jan. 1807, on the death of Dr. Edward Whitaker Gray, and in January 1807 he became a member of the council. Davy's earliest experiments in galvanism had been made in 1800, when he mentions 'unhoped-for successes' in a letter to Gilbert. He was beginning fresh galvanic experiments in 1806, when the laboratory books of the Royal Institution show that in October he 'tried to decompose phosphorus by the galvanic fluid.' The discoveries of Volta at this time were exciting the attention of men of science. Davy worked zealously in developing the chemical action of the voltaic battery. He was now working with a battery of a hundred plates of six inches diameter. On 12 Nov. he informs his friend Mr. Pepys: 'I have decomposed and recomposed the fixed alkalies (potash and soda), and discovered their bases to be two new inflammable substitutes (potassium and sodium) very like metals, but one of them lighter than ether, and infinitely more combustible; so that there are two bodies decomposed, and two new elementary bodies found. Davy commenced those inquiries on the 16th and obtained his great result on 19 Oct. 1807. Shortly after this John George Children [q. v.] constructed the great battery with which his name is associated. This battery doubtless led to the collection, by the managers of the Royal Institution, of a fund for the construction of a yet more magnificent battery. It consisted of two hundred instruments connected together in regular order, each composed often double plates arranged in cells of porcelain, and containing in each plate thirty-two square inches, so that the whole number of double plates was two thousand, and the whole surface 128,000 square inches. With this powerful battery Davy repeated all his previous experiments, he instituted several with the hope of decomposing nitrogen, he most satisfactorily proved the actual character of oxymuriatic acid, he completely overthrew the theories of the Stahlian school, demonstrated in the most conclusive manner the existence of chlorine as a new elementary body, and proved its value as a bleaching agent. The announcement of a theory so adverse to the universal faith of chemists as that of chlorine being a simple substance which, combining with hydrogen, formed muriatic acid, was received with a storm of objections; but these were all refuted by vigorous methods of inquiry, and ultimately all the philosophers yielded their assent to Davy's views.

On 19 Nov. 1807 Davy explained all his experiments and discoveries in electricity before the Royal Society in the Bakerian lecture. His fame became European. Napoleon, then first consul, founded a prize of three thousand francs for the best experiments made on the galvanic fluid. Twelve months after the publication of Davy's lecture the Institute of France awarded him the Napoleon prize 'for his discoveries announced in the "Philosophical Transactions" for the year 1807.' In connection with galvanic phenomena Davy continued to achieve triumphs which greatly increased his fame, and considerably added to our stores of scientific truth.

At the close of 1807 Davy had a severe illness, occasioned probably by exposure to the unhealthy atmosphere of Newgate prison, the disinfecting of which he had undertaken. He was not able to resume his work until 19 April 1808, when he was again using his battery of 520 pair of plates. Through the spring and summer a series of beautiful experiments were made on ammonia and nitrogen. Davy tells Children, in a letter written at this time, that 'he hoped to show him nitrogen as a complete wreck, torn to pieces in different ways.' He was not successful, however, in decomposing nitrogen, but in his Bakerian lecture in December 1808, in which he elucidated the 'elementary matter of ammonia, the nature of phosphorus, sulphur, charcoal, and the diamond,' and in his fourth Bakerian lecture in 1809, he dealt particularly with 'the metallic bodies from the alkalies and earths, and on some combinations of hydrogen.' The Bakerian lecture for 1810 was devoted to the 'combinations of oxymuriatic gas and oxygen.' In that year the Dublin Society raised by subscription the sum of four hundred guineas, which they offered to Davy if he would deliver some lectures respecting the recent discoveries made by him in electro-chemical science. The 'Farming Society of Ireland,' being desirous of availing themselves of this opportunity, applied to Davy for six lectures on the application of chemistry to agriculture. Davy received 750l., and a large surplus went to defray expenses. In the following year Davy delivered two distinct courses in Dublin, one on the 'Elements of Chemical Philosophy,' and the other on 'Geology,' the proceeds from these lectures being 1,101l. 2s. Before Davy quitted Dublin the provost and fellows of Trinity College conferred upon him the honorary degree of LL.D. In the month of August Davy's opinion was requested by a committee as to the most satisfactory method of ventilating the House of Lords. Davy's recommendation was adopted, but it did not prove successful. On 8 April 1812 he was knighted by the prince regent. On the day following he delivered his farewell lecture at the Royal Institution. The minutes of that institution inform us that on 5 April 1813 Davy begged leave to resign his situation of professor of chemistry, when Earl Spencer moved 'that, in order more strongly to mark the high sense entertained by this meeting of the merits of Sir H. Davy, he be elected honorary professor of chemistry.'

On 11 April 1812 Davy married Mrs. Apreece, the widow of Shuckburgh Ashby Apreece, and the daughter and heiress of Charles Kerr [see Davy, Jane, Lady] of Kelso. His biographer Dr. Paris remarks 'that other views of ambition than those presented by achievements in science had opened upon his mind; the wealth he was about to command might extend the sphere of his usefulness, and exalt him in the scale of society; his feelings became more aristocratic, he discovered charms in rank which had before escaped him, and he no longer viewed patrician distinction with philosophic indifference.'

Davy had already discovered the talents of Faraday, for whom he obtained an appointment as assistant in the laboratory of the Royal Institution. In October he went abroad, taking Faraday with him. Davy did not allow his independent position to interfere with his scientific inquiries. While abroad he sent seven papers to the Royal Society. He published his 'Elements of Chemical Philosophy,' and in March 1813 he issued his 'Elements of Agricultural Chemistry,' the substance of a course of lectures delivered for ten successive seasons before the board of agriculture. In 1813 Davy was evidently alarmed at its being supposed that a gunpowder which he had manufactured in partnership with J. G. Children and Burton was 'supposed to be sold by' him, and desires it to be made public that his assistance had been gratuitous. The correspondence on the 'Ramhurst gunpowder' is painfully significant of the growing influence of wealth and position. While travelling on the continent during the war, by permission of Napoleon, Davy was patronised by all the scientific men of the day. The favour of his company was invited by the Philomathic Society, at which thirty-three members were present, among whom were Ampère, Cuvier, Chevreuil, and Humboldt. At the dinner the toast of the Royal Society of London was given, to which Davy returned thanks. Ampère at this time furnished Davy with a small portion of iodine, recently discovered by Courtois. On 13 Dec. a letter was read by Cuvier, which he had received from Davy, giving a general view, of the chemical nature and relations of iodine, and in January 1814 he communicated to the Royal Society of London an elaborate memoir on the same element. On 13 Dec. 1813 Davy was elected a corresponding member of the first class of the Imperial Institute.

While in Italy Davy made experiments on the torpedo, and he worked in the laboratory of the Accademia del Cimento on the combustion of the diamond. The results were communicated to the Royal Society. At Pavia he met Volta, who awaited in full dress the arrival of Davy. On the introduction of the English philosopher, who was meanly dressed, Volta started back in astonishment, and for some moments was unable to address him. On 23 April 1813 Davy returned to London, having made experiments on the colours used by the ancients and several other matters of interest, the results of which he communicated to the Royal Society.

On 3 Aug. 1815 Davy acknowledges a letter which he had received from the Rev. Dr. Gray, directing his attention to the destruction of human life by explosions in working our coalmines. Davy gave immediate attention to the subject, and being supplied with specimens of firedamp by John Buddle of Newcastle [q. v.], he began to investigate its nature. On 31 Oct. 1815 Davy communicated to Dr. Gray that he had discovered a safe lamp, on 2 Nov. read a paper on the firedamp before the Royal Society, and on 14 Dec. he sent to his friend Dr. Gray some models of lamps and lanterns, based on his discovery that 'the firedamp will not explode in tubes or feeders of a certain small diameter.' Glass tubes were employed at first, but Davy soon found that metallic tubes, such as wire gauze, resisted equally well the passage of flame. This led to his surrounding the flame of his lamp with wire gauze. The explosive gas freely entered the lamp and exploded within it, the explosion not passing outward through the apertures of the wire. Davy's triumph was somewhat clouded by the claims put forward by Dr. Clanny and George Stephenson [q. v.] The lamp devised by Dr. Clanny in no respect resembled that of Davy [see Clanny, William Reid], and that of Stephenson differs from it in several particulars. Stephenson's lamp dates its origin from 21 Oct. 1815, and has many claims to attention. Buddle on 27 Oct. 1816 wrote to the Rev. Dr. Gray, informing him that at a meeting of the coal owners it had been suggested that a subscription should be made for the purpose of presenting to Davy a testimonial which would 'show distinctly the real opinion of the coal trade as to the merit of his invention,' the safety lamp. On 11 Jan. 1817 the subscription amounted to nearly 1,500l. On 26 Sept. 1817 a dinner was given to Davy, at which the coalowners presented him with a service of plate, and a resolution was passed ascribing the merit of the discovery to Davy alone. Numerous modifications of the safety lamp have been introduced from time to time. The royal commission on mines, 1866, during their inquiry collected no fewer than two hundred lamps, many of them exhibiting a high order of safety.

Davy communicated several papers to the Royal Society in connection with this inquiry, and the president and council adjudged to him the Rumford medals. Upon the advice of his friends the principal memoirs were collected and published in an octavo volume entitled 'On the Safety Lamp for Coal Mines, and some Researches on Flame,' London, 1818. Davy was created a baronet on 20 Oct. 1818. In 1813 the Geological Society of Cornwall was established at Penzance. Davy naturally manifested considerable zeal in its progress. He made a handsome donation to its funds, contributed a suite of specimens illustrative of the volcanic district of Naples, and communicated a memoir on the geology of Cornwall, which was printed in the first volume of the society's 'Transactions.' On 26 May 1818 Davy embarked at Dover for the continent, in order to proceed to Naples, his object being to unfold and render legible the ancient papyri deposited in the museum of that city. He visited Herculaneum, and afterwards commenced his experiments on unrolling the papyri. He communicated to the Royal Society the results of his inquiries and experiments on 15 March 1821, which were published in the 'Transactions' of that year. The final result of this inquiry was not successful or satisfactory. Davy succeeded in partially unrolling twenty-three manuscripts, from which fragments of writing were obtained, but unpleasant circumstances interfered with his inquiries, and he concluded that 'it would be both a waste of public money and a compromise of our own character to proceed.'

Davy returned to England in 1820, and on 20 Nov. was elected to succeed Sir Joseph Banks in the presidential chair of the Royal Society. Unfortunately, conflicting opinions arose respecting the management of the Royal Institution, and party spirit was kindled between the Albemarle Street members and the fellows of the Royal Society. This was a source of very considerable annoyance to the president. Davy, nevertheless, continued to give close attention to science. The discovery by Oersted of the relation between magnetism and electricity claimed his immediate attention, and in 1820-21 and 1823 he communicated his 'Researches on Electro-magnetic Phenomena' to the Royal Society. In these inquiries he received much assistance from Faraday, as well as in those on the condensation of the gases, on which subject he read two papers before the Royal Society.

The rapid decay of the copper sheathing on the bottoms of our ships was a problem submitted by the government to the Royal Society, and a committee was formed to investigate it. In 1823 Davy commenced his inquiry into this matter, and prosecuted it with his usual zeal. The results obtained appeared highly satisfactory. A piece of zinc, not larger than a pea, was found adequate to preserve forty or fifty square inches of copper. Numerous experiments were made — and with results equally conclusive — of Davy's theory, based on the electrical conditions of the two metals. Several ships in the royal navy were fitted with Davy's protectors, but the government in 1825 ordered the discontinuance of them on all sea-going ships. Shell-fish of various kinds were found to adhere to the copper plates, which were prevented from oxidising by the electrical action of the metals, and this greatly interfered with their sailing powers. These protectors were still continued on ships in harbour, but the plan was finally abandoned on those in September 1828. Davy's vexation was great, and the consequences were soon apparent in his failing health. At the end of 1826 his complaint assumed a more alarming form. Feeling more unwell than usual while on a visit to Lord Gage, he resolved to return to London, and he was seized while on the journey with an apoplectic attack. Prompt attention arrested the more serious symptoms, but paralysis ensued. As soon as possible it was thought desirable that Davy should winter in Italy. He wrote from Ravenna on 14 March 1827 stating his intention to remain there until the beginning of April and then to go to the Alps. Feeling that his recovery was slow, he determined to resign the chair of the Royal Society, and he wrote to that effect to Davies Gilbert on 1 July 1827. On 6 Nov. 1827 a resolution passed, at a very full meeting, appointed Gilbert to fill the chair until the anniversary meeting. Davy had contribute forty-six memoirs and lectures to the 'Transactions' of the Royal Society, and he published nine separate works on science.

Davy returned to England, and, writing from Park Street on 29 Oct. 1827, he expresses himself to his friends hopefully, but complains of a want of power and frequently longs 'for the fresh air of the mountains.' Natural history was the principal subject of his contemphitions at this time, and m this period he completed and published his 'Salmonia, or Days of Fly-fishing,' a work of great scientific interest and happily popular in its treatment. He was a skilful angler, and found time for the sport in the intervals of his scientific labours. On 20 March 1828 a paper by Davy, 'On the Phenomena of Volcanoes, was communicated to the Royal Society. Shortly after this he left England. On 6 Feb. 1829 he writes to his constant friend, Thomas Poole, a letter from Rome, in which he exclaims : 'Would I were better ... but I am here wearing away the winter, a ruin amongst ruins.' He still continued to work slowly ; he investigated the electricity of the torpedo, and recognised a new species of eel — a sort of link between the conger and the muræna of the ancients. A paper on these inquiries was read before the Royal Society on 20 Nov. 1829. During this period of melancholy repose Davy wrote 'Consolations in Travel, or the Last Days of a Philosopher.' His brother, Dr. Davy, who edited the work after the death of Sir Humphry, informs us that it was finished at the very moment of the author's last illness. On 26 Feb. he dictated a letter to his brother, chiefly on the torpedo. He endeavoured to write a postscript, and he did write 'My dear John.' He then dictated 'I am dying ; come as quickly as you can.' Dr. Davy reached his brother on 16 March, and Sir Humphry was greatly interested the next day with the dissection of a torpedo. He rallied after this attack, and on 20 April left Rome, reaching Geneva on 28 May. He died at half-past two on the following morning. He was buried in the cemetery of Plain-Palais. A tablet placed in Westminster Abbey by his widow, and the statue placed on the spot in the centre of Penzance on which his earliest days were passed, are the only outward signs of our appreciation of a philosopher of whom it has been justly said : 'He was not only one of the greatest, but one of the most benevolent and amiable of men.'

[Paris's Life of Sir Humphry Davy, bart. ; John Davy's Memoirs of the Life of Sir Humphry Davy, bart., LL.D., F.R.S. ; Collected Works of Sir Humphry Davy ; Bence Jones's The Royal Institution; Royal Society's Cat. of Scientific Papers ; Weld's History of the Royal Society ; Fragmentary Remains, Literary and Scientific, of Sir Humphry Davy, edited by John Davy; Philosophical Magazine, 1866 ; information from Davy's family.]

R. H-t.