Chapter IV: Part 4

Besides his scientific attainments, Hatchett possessed great conversational powers; he was good-humoured, full of drollery, and never at fault for some jocular or pleasant story, to amuse the company he might be with. At the Royal Society Club, of which he was a member, he was a great favourite, particularly with Sir Joseph Banks, who, after Dr. Johnson, used to call him a clubable man. Sir John Barrow gives the following anecdote:--That "one day, at the club, Hatchett amused us with the story of a dream, which he prefaced by saying that, although it was 'such stuff as dreams are made of,' it still contained a reality in its conclusion, which had very much distressed him. He dreamt that he had lost his way, but came to a dark and dismal-looking building, into which he passed through a forbidding sort of gate, opened by a black-looking porter, who closed it immediately after him. He walked on, and everywhere observed clumps of ill-looking people skirmishing and fighting, while a little beyond were other groups, weeping and in great distress; further on still were flames of fire. Beginning to think he had got into a very bad place, he endeavoured to retrace his steps and get out again; but the black doorkeeper refused to let him pass. A furious fight ensued, and he pummelled the negro-looking rascal, first with one fist and then with another. At length he was brought to his senses by a scream, which, to his dismay, proceeded from his poor wife, and he found that, instead of pummelling the black doorkeeper, he had given Mrs. Hatchett a black eye."

In 1809, Mr. Hatchett was elected one of the chosen few of the Literary Club, originally instituted by Dr. Johnson and Sir Joshua Reynolds; and on the death of Dr. Burney, in 1829, was appointed to the chief official station of treasurer to the club.

In 1810 he took up his residence at Belle Vue House, Chelsea, where he continued for the remainder of his life, which terminated in 1847, Mr. Hatchett having then attained the advanced age of eighty-two.--_Sketches of the Royal Society and Royal Society Club, by Sir John Barrow, Bart., F.R.S._ London, 1849.

WILLIAM HENRY, M.D., F.R.S., &c.

Born December 12, 1774. Died September 2, 1836.

Dr. William Henry, the distinguished chemical philosopher, was born at Manchester. His father, Mr. Thomas Henry, was a zealous cultivator of chemical science. The earliest impressions of Henry's childhood were, therefore, such as to inspire interest and reverence for the pursuits of science; and he is said, when very young, to have sought amusement in attempting to imitate, with such means as were at his disposal, the chemical experiments which his father had been performing. A severe accident which occurred in early life, by disqualifying him for the active sports of boyhood, also contributed to determine his taste for books and sedentary occupations. This injury, occasioned by the fall of a heavy beam upon his right side, was of a very serious nature, and materially checked his growth; it left as its consequence acute neuralgic pains, which recurred from time to time, with more or less severity, during the remainder of his life.

Dr. Henry's earliest instructor was the Rev. Ralph Harrison, who possessed considerable repute as a teacher of the ancient languages, and was considered at that period to be one of the best instructors of youth in the North of England. Immediately on leaving Mr. Harrison's academy at Manchester, Henry had the good fortune to become the private secretary of Dr. Percival, a physician of great general accomplishments and refined taste, whose example and judicious counsels were most instrumental in guiding the tastes of his young companion, and in establishing habits of vigilant and appropriate expression. In this improving residence Dr. Henry remained for the space of five years; he was then removed, in the winter of 1795-6, to the University of Edinburgh, after having acquired some preliminary medical knowledge at the Infirmary at Manchester. Prudential considerations compelled him to leave the University at the end of a year, and commence general medical practice in company with his father. A few years' experience, however, showed the inadequacy of his delicate frame to bear up against the fatigues of this branch of the medical profession, and he was permitted, in the year 1805, to return to the University, at that time adorned by the learning of Playfair and Stewart. So powerful was the stimulus given to his mental powers during his residence at the University, that he often declared that the rest of his life, active as it was, appeared a state of inglorious repose when contrasted with this season of unremitted effort. The period intervening between Dr. Henry's two academic residences, although passed in the engrossing occupations of his profession, to which was added the superintendence of a chemical business previously established by his father, was yet marked by several important contributions to science. In 1797 he communicated to the Royal Society an experimental memoir (the first of a long series with which he enriched the 'Transactions' of that body), the design of which was to re-establish the title of carbon to be ranked among elementary bodies, which had been denied by Austin, Beddoes, and other eminent chemists. In this paper he subsequently discovered a fallacy in his own reasoning, which he exposed before it had been detected by any other chemist. In 1800 he published in the 'Philosophical Transactions' his experiments on muriatic acid gas, and in 1803 made known to the Royal Society his elaborate experiments on the quantity of gases absorbed by water at different temperature and under different pressures, the result of which was the establishment of the law that "water takes up of gas, condensed by one, two or more additional atmospheres, a quantity which would be equal to twice, thrice, &c. the volume absorbed under the ordinary pressure of the atmosphere." In 1808 Henry was elected a Fellow of the Royal Society, and in the same year described in their 'Transactions' a form of apparatus adapted to the combustion of larger quantities of gases than could be fired in eudiometric tubes. This apparatus, though now superseded, gave more accurate results than had ever before been attained. In the following year (1809) the Copley gold medal was awarded to him for his valuable contributions to the 'Transactions' of the Royal Society. For the next fifteen years Dr. Henry continued his experiments on gases, making known to the Society the results from time to time. In his last communication, in 1824, he claimed the merit of having conquered the only difficulty that remained in a series of experiments on the analysis of the gaseous substances issuing from the destructive distillation of coal and oil--viz., the ascertaining by chemical means the exact proportions which the gases, left after the action of chlorine on oil and coal gas, bear to each other. This he accomplished by skilfully availing himself of the property (recently discovered by Döbereiner), in finely divided platinum, of causing gaseous combinations, and he was thus enabled to prove the exact composition of the fire-damp of mines. All the experiments of Dr. Henry which have been previously alluded to bore upon äeriform bodies; but although these were his favourite studies, his acquaintance with general chemistry is proved by his 'Elements of Experimental Chemistry,' to have been both sound and extensive. This work was one of the first on chemical science published in this country, which combined great literary elegance with the highest standard of scientific accuracy. His comparative analysis of many varieties of British and foreign salts were models of accurate analysis, and were important in dispelling the prejudices then popular in favour of the latter for economical purposes. His 'Memoir on the Theories of Galvanic Decomposition' earned the cordial approval of Berzelius, as being among the first maintaining that view which he himself so earnestly supported.

It is greatly to be regretted that Dr. Henry did not contribute more to the literature of science, as he appears to have been eminently fitted, both by natural tastes and by after culture, to excel in this particular respect; especially is it to be regretted that he did not live to carry out the great literary project for which he had collected materials--a history of chemical discovery from the middle of the last century. He could have made it one of the most popular books in our tongue.

In the general intercourse of society Dr. Henry was distinguished by a polished courtesy, by an intuitive propriety, and by a considerate forethought and respect for the feelings and opinions of others; qualities issuing out of the same high-toned sensibility, that guided his taste in letters, and that softened and elevated his whole moral frame and bearing. His comprehensive range of thought and knowledge, his proneness to general speculation in contradistinction to detail, his ready command of the refinements of language, and the liveliness of his feelings and imagination, rendered him a most instructive and engaging companion. To the young, and more especially to such as gave evidence of a taste for liberal studies, his manner was peculiarly kind and encouraging. In measuring the amount and importance of his contributions to chemical knowledge, it must be borne in mind, that in his season of greatest mental activity, he never enjoyed that uncontrolled command of time and that serene concentration of thought which are essential to the completion of great scientific designs. In more advanced life, when relieved from the duties of an extensive medical practice and other equally pressing avocations, growing infirmities and failing bodily power restrained him to studies not demanding personal exertion, and even abridged his season of purely mental labour. That amid circumstances so unfriendly to original and sustained achievements in science, he should have accomplished so much, bears testimony to that energy of resolve, that unsubdued ardour of spirit which ever glowed within him, urging him steadily onwards in the career of honourable ambition, and prompting exertions more than commensurate with the decaying forces of a frame that had never been vigorous. At intervals during his whole life, Dr. Henry suffered severely from the effect of the accident already mentioned. The paroxysms of intense neuralgic agony which attacked him, at length caused the whole nervous system to be so irritated as to deprive him of sleep, and cause his death in September, 1836, at the age of sixty-one.--_Biographical Account of the late Dr. Henry, by his son, William Charles Henry, M.D., F.R.S., &c._--_Encyclopædia Britannica_, Eighth Edition.

SIR WILLIAM HERSCHEL, D.C.L., F.R.S., &c.

Born November 15, 1738. Died August 23, 1822.

Authentic particulars respecting both the early and private life of this great astronomer are sadly deficient; his scientific works are, however, of a world-wide reputation, and it is with these that we are chiefly concerned. William Herschel was born at Hanover, and was one of a numerous family, who supported themselves chiefly by their musical talents. At the age of fourteen William was placed, it is said, in the band of the Hanoverian regiment of Guards, which he accompanied to England at a period variously stated from 1757 to 1759. On his arrival he remained for some time at Durham, and was subsequently, for several years, organist at Halifax, where he was also employed in teaching music and studying languages. At length, about the year 1766, he found himself in comparatively easy circumstances, as organist of the Octagon Chapel at Bath. Here Herschel began to study earnestly the science of astronomy; and feeling the necessity of obtaining a good telescope, the purchase of which would be beyond his means, he determined to make one himself. After many trials, he succeeded in 1774 in executing with his own hands a reflecting telescope, and soon acquired so much dexterity, as to construct instruments of ten and twenty feet in focal length.

In the year 1780 he contributed his first paper, 'On the Variable Star in Cetus,' to the Royal Society; and on the 13th of March, 1781, announced to the world his discovery of a supposed comet, which, on further examination, proved to be a planet exterior to Saturn, now named Uranus.[20] This fortunate success was the first addition to the number of primary planets since a period of an immemorial antiquity, and it speedily made the name of Herschel famous.

George III. took the new astronomer under his protection, and attached him to his court, bestowing on him the title of astronomer to the king, with a salary of 400_l._ a year. It is difficult to estimate the amount of benefit thus conferred on astronomy by the award of this pension; for nothing short of the entire devotion of a lifetime, could have produced such results as we owe to Herschel. His contributions to the 'Philosophical Transactions' alone amount to sixty-nine in number, and may give some idea of the unwearied activity of the author; they range over a period of thirty-five years, commencing in 1780 and terminating in 1815. The numerous bodies which he added to the solar system, make that number half as large again as he found it. Including Halley's comet, and the four satellites of Jupiter and five of Saturn, the number previously known was eighteen, to which Herschel added nine--namely Uranus and six satellites, and two satellites of Saturn. His discovery of the rotation of Saturn's ring, his measurements of the rotation of Saturn and Venus, his observations of the belts of the former, and his conjectural theory--derived from observation--of the rotation of Jupiter's satellites, with a large number of minor observations, prove that no one individual ever added so much to the facts on which our knowledge of the solar system is founded. His leading discoveries in siderial astronomy include--the discovery of binary systems of stars, and the orbits of several revolving stars; the discovery and classification of a prodigious multitude of nebulæ; the law of grouping of the entire firmament, and its connection with the great nebula of the Milky Way; and lastly, the determination of the motion of our sun and system in space, and the direction of that motion.

Herschel's magnificent speculations on the Milky Way, the constitution of nebulæ, &c., first opened the road to the conception, that what was called the universe was, in all probability, but a detached and minute portion of that fathomless series of similar formations which ought to bear the name. Imagination roves with ease upon such subjects; but before Herschel's observations, even that daring faculty would have rejected ideas which afterwards proved to be but sober philosophy. These great and arduous enquiries occupied Herschel during nearly the whole of his scientific career, extending to almost half a century, and, excepting the continuation of his labours by his illustrious son, Sir John, little has been added to our knowledge of 'the constitution of the heavens' since his death.

As an optician, Herschel deserves equal notice for the wonderful improvements which he effected in the dimensions and magnifying power of telescopes, and by the skill with which he applied them to celestial observations. The reflecting telescope was the one to the improvement of which he so successfully devoted himself; and the real secret of his success in this, was his astonishing perseverance; his determination being to obtain telescopes of twenty feet focal length or more, and of a perfection equal or superior to the small ones then in use. He himself relates, that whilst at Bath he had constructed 200 specula of seven feet focus, 150 of ten feet, and about 80 of twenty feet; a proof of extraordinary resolution in a man of limited means, and at that time engaged in a laborious profession.

Herschel at last succeeded in constructing his enormous telescope of forty feet focal length, which he erected in the grounds of his house at Slough. This instrument was begun in 1785, and finally completed on August 28th, 1789, on which day Herschel discovered with it the sixth satellite of Saturn; the diameter of the tube was 4 feet 10 inches, the speculum having a useful area of 4 feet: the total cost was 4000_l._, which was entirely defrayed by the liberality of George the Third.

After the award of the king's pension, Sir William Herschel fixed his residence at Slough, near Windsor, his family consisting at first of one of his brothers, and his sister, Miss Caroline Herschel, who was his coadjutor and assistant in his computations and reductions, and was also actively employed in astronomical observation, being the discoverer of more than one comet. Herschel married a widow lady, Mrs. Mary Pitt, and left one son, the present Sir John, whose name has long been known to the public as one of the most active and successful adherents of science that our day has produced.

Dr. J. D. Forbes thus sums up the philosophical character of Sir William Herschel:--

"He united, in a remarkable degree, the resolute industry which distinguishes the Germans, with the ardour and constancy which has been thought characteristic of the Anglo-Saxon. From his native country he brought with him the boldness of speculation which has long distinguished it, and it is probable that he had also a vigorous and even poetical imagination. Yet he was ever impatient until he had brought his conjectures to the test of experiment, and observation of the most uncompromising kind. He delighted to give his data a numerical character, and where this was (by their nature) impossible, he confirmed his descriptions by reiterated observation, in different states of weather, with different telescopes, apertures, and magnifying powers; and with praiseworthy fidelity he enabled his readers to form their own judgment of the character of his results, by copious and literal transcripts from his journals."

Herschel died peacefully at Slough, at the advanced age of eighty-three, on the 23rd of August, 1822, only one year after the publication of his latest memoir in the 'Transactions' of the then recently formed Astronomical Society, of which he was the first president.--_Sixth Dissertation, by James David Forbes, D.C.L., F.R.S., &c., Encyclopædia Britt._, eighth edition.--_English Cyclopædia._ London, 1856.--_Weld's Hist. of Roy. Society._

EDWARD CHARLES HOWARD, F.R.S.

Born May 28, 1774. Died September 28, 1816.

Mr. Howard was born at Darnell, in the parish of Sheffield, and was the third brother of the twelfth Duke of Norfolk. His name has become intimately connected with the manufacture of sugar, from the many improvements which he introduced into the old processes for the refinement of this most important article of commerce, and especially by his invention of the vacuum-pan.

It is related, on the authority of the late Mr. C. Few, that Mr. Howard's attention was drawn towards this subject by Mr. Charles Ellis, who, on the occasion of an immense quantity of West India sugar being in bond, and for which the revenue could find no market, recommended Howard, whose talents as a practical chemist Mr. Ellis was well acquainted with, to try and see if he could not relieve the Government warehouses, by converting the raw sugar into some kind of manure, and thus avoid the duty and render the article saleable. While experimenting for this purpose, Mr. Howard accidentally discovered his process of purifying sugar, for which, in conjunction with certain sugar refiners, he took out patents, and ultimately realized a considerable fortune.

Howard's vacuum-pan was patented in 1812; it depends for its action on the principle that liquids boil at temperatures dependent on the pressures they have to sustain. Thus water, under the ordinary pressure of the atmosphere (30 inches barometer), boils at 212° F., whereas in vacuo it will boil at about 80°; consequently a comparatively low temperature will effect the boiling of sugar-syrup in vacuo, evaporation will proceed far more safely than in the old process of heating the syrup in open pans, and the percentage of waste will be greatly reduced, rendering the manufacture highly profitable in a commercial point of view.

Mr. Howard died at the early age of forty-two, and was buried at St. Pancras, Middlesex. He left one son, and a daughter, Julia, who was married in the year 1829 to the Hon. Henry Stafford Jerningham, afterwards Lord Stafford.

CAPTAIN J. HUDDART, F.R.S.

Born Jan. 11, 1740. Died August 19, 1816.

Joseph Huddart was born at Allonby in Cumberland. His Father, who was a shoemaker and farmer, desiring to give his son the best education in his power, sent him to a day-school kept by Mr. Wilson, the clergyman of the village. Here young Huddart acquired a knowledge of the elements of mathematics, including astronomy, sciences in which he attained great proficiency in after life. When quite a boy, Huddart gave indications of an original mind, combined with great industry and unwearied patience. Having fallen in with a treatise by Mungo Murray on ship building, he was so pleased with its clear directions, that he set to work and succeeded, after immense labour and ingenuity, in making a model of a seventy-four gun-ship, with ribs, planks, and bolts complete. When engaged in herding his father's cows, he used to carry out into the country a desk of his own manufacture, employing his time in reading, and mathematical drawing and calculations.

As Huddart grew up he evinced a strong bias for a sea-faring life, and an event occurred in 1756 which decided his future career. In that year large shoals of herrings came into the Solway Firth, and the elder Huddart took advantage of the circumstance to trade in conjunction with a Herring Fishery Company, while his son took his place with others in the boats, and soon displayed so much skill and ability in their management that he became noted among his fellows for superiority of knowledge in nautical matters. Young Huddart continued more or less in this new employment until his father's death, in 1762, when he succeeded to a share in the fishery, and at once took the command of a sloop employed in carrying the salted herrings to Cork and other parts of Ireland, for the supply of the West India markets.

These voyages gave him a thorough knowledge of St. George's Channel, convinced him of the insufficiency of the charts then in use, and ultimately led to his making a complete survey of that sea, and to the subsequent publication of his own most valuable chart. In 1768 Huddart, with the assistance of his uncle, designed and built a vessel for himself, and named it the Patience, every timber in it having been moulded with his own hand. In this vessel he made his first voyage to North America, and continued to sail in her until the year 1771, when he was induced by Sir Richard Hotham, with whom he had become acquainted, to enter the East India Mercantile Marine, in which service he continued for many years, and realized a considerable independency.

Captain Huddart's scientific knowledge and high character introduced him into the Trinity House as an Elder Brother, and also into the Committee of the Ramsgate Harbour Trust, and into the London and East India Dock Directions. At the Trinity House all inquiries relating to lights, lighthouses and charts were chiefly referred to him, while the lighthouses on Hurst Point were built under his superintendence and immediate direction.

On retirement from the East India Company's service, Huddart engaged again in his favourite pursuit of ship building, making many practical experiments to determine the lines, which consistent with stability and capacity for stowage would give to vessels the greatest velocity through the water. But that which constitutes Captain Huddart's chief claim on the gratitude of posterity are his great improvements and inventions in the manufacture of Cordage; before his time nothing worthy of the name of machinery had been applied to rope-making, and to him was reserved the honour of bringing the wonderful power of Watt's steam engine to bear upon this most important article of manufacture.

Captain Huddart's attention was first drawn towards the subject during a voyage from India to China through the Straits of Sunda, where the ship he commanded was frequently compelled to anchor. When the anchor was weighed, the outer yarns of the cable were often found to be broken, and on opening a piece of cable to find out the cause, Huddart's attention was forcibly drawn to the fact that rope as then manufactured, bore almost the entire strain on the outer yarns of the strands, from the yarns being originally of the same length, and the strand in the process of twisting becoming shortened. He determined to remedy this, and ultimately constructed a machine which, by means of what he called a register plate, gave to every yarn the same strain, and its proper position in the strand which was compressed through a tube into the desired form.

Government refusing to take up this valuable invention, a company was formed by Huddart's friends for the manufacture of rope upon his new principle. These gentlemen built a factory at Limehouse, which was established under the name of Huddart & Co.

Captain Huddart now devoted himself to the further development of his valuable invention; he contrived a registering machine whereby the yarns were formed as they came out of the tar-kettle, the tar being kept at the temperature (212-220° Fah.) he found by experiment to be sufficient for the required purpose, without injuring by too great heat the fibres of the rope.

He also constructed a laying machine, which gave the same length and twist to every strand, and an uniform angle and pressure to the rope or cable. These improvements involved the manufacture of much beautiful machinery, which was made after Huddart's design and under his own personal superintendance.[21]

Captain Huddart lived to an advanced old age, and even in his last illness his disposition to inquire into causes and effects did not forsake him, as his body gradually wasted away, he caused himself to be weighed from time to time, noting thereby the quantity of moisture which escaped by the breath and insensible perspiration. He died at Highbury Terrace, London, at the age of seventy-six, and was interred in a vault under St. Martin's Church, in the Strand.--_Memoir of Capt. Jos. Huddart, by Wm. Cotton, D.C.L._ London, 1855.

EDWARD JENNER, M.D., L.L.D., F.R.S., &c.

MEMBER OF THE INSTITUTE OF FRANCE.

Born May 17, 1749. Died January 26, 1823.

Edward Jenner, who by his discovery of vaccination has pre-eminently acquired a right to the title of the "Benefactor of Mankind," was born at the vicarage house of Berkeley, in Gloucestershire, and was the third son of the Rev. Stephen Jenner, rector of Rockhampton, and vicar of Berkeley. Jenner's father died when he was only five years old, leaving him to be brought up under the care of his uncle. At eight years of age he was put to school at Wotton-under-Edge, from whence he was removed shortly afterwards to the care of Dr. Washborn, at Cirencester. Jenner early displayed that taste for natural history which afterwards formed so marked a feature in his character. Before he was nine years old he had made a collection of the nests of the dormouse, and when at Cirencester used to spend his hours of recreation in searching for the fossils which abound in that district.

After the completion of his scholastic education, Jenner removed to Sudbury, near Bristol, where he acquired the elements of surgery and pharmacy under Mr. Ludlow, an eminent surgeon in the neighbourhood. Having completed his term with this gentleman, he went to London and became a pupil of the celebrated John Hunter, in whose family he resided for two years, laying the foundation of an intimate friendship only broken by Hunter's death. Under the tuition of this distinguished anatomist he acquired an almost unrivalled skill in minute dissections and delicate injections of parts; and when, in the year 1771, Captain Cook returned from his first voyage of discovery, the valuable specimens of Natural History, which had been collected by Sir Joseph Banks, were in a great measure arranged and prepared by Jenner, who was recommended by Mr. Hunter for that purpose. In executing this task, he evinced so much dexterity and intelligence, that he was offered the post of Naturalist in the next expedition, which sailed in 1772. Jenner, however, refused the offer, and determined to fix his abode at the place of his birth. He returned to Berkeley when about twenty-four years old, and at once commenced practice as a country surgeon. His first attempts were very successful; and as he added to his professional skill the manners of a thorough gentleman, and the information of a scholar, he became a welcome guest in the most distinguished families. He was in the habit at this time of cultivating the art of poetry, and used to send his compositions to his friends in the ordinary interchange of literary correspondence. He was likewise clever at an epigram or a ballad, and had a natural taste for music, being able to play on the flute and violin, and sing his own verses with considerable taste and feeling. Such was the attachment of Jenner's friends to him at this period of his career, and so highly did they value his amusing and interesting conversation, that, when he had called at their houses, either as a visitor or in his professional capacity, they would accompany him, on leaving, many miles on his way home, and this too, often at midnight, in order that they might prolong the pleasure derived from his company and conversation.

Although Jenner's time was chiefly occupied with his professional duties, he still kept up a constant and regular correspondence with his friend John Hunter on different scientific subjects. He managed also to find leisure to institute many experiments and observations in natural history, one of the results of which was his account of the Cuckoo, a most carefully elaborated essay, and which has always been considered as a model of accurate observation. This paper was read to the Royal Society on the 10th of March, 1788, and printed in their 'Transactions.' It explained the habits of this curious bird very satisfactorily, and its publication at once secured the author a considerable reputation as a Naturalist. As this paper appears not to be very generally known, the following account taken from it may be interesting:--

"The cuckoo furtively deposits her egg in the nest of another bird; it is done not that her offspring may be a sharer of the care of the foster-parent, but that it may engross it entirely to the total destruction of its own natural offspring. A perversion of all the maternal instincts is a most remarkable result of this vicarious incubation. The hedge-sparrow, or other birds whose nests have been visited by the cuckoo, actually sometimes eject their own eggs to make room for the new guest; but it occasionally happens that this is not done; the eggs are not disturbed, and the process of hatching is allowed to go on regularly, and the young sparrows and the cuckoo emerge from the shell about the same time. This event, when it is permitted to happen, does not at all improve the condition of the former; on the contrary, it only exposes them to greater sufferings. The size of the egg of the cuckoo does not vary much from that of the bird in whose nest it is deposited. When the young sparrow, therefore, and the intruder first come into life, they are pretty much on an equality; but unhappily for the foster-brethren, this equality does not last long: the cuckoo's growth rapidly outstrips that of his companions, and he immediately exercises his new powers with abundant selfishness and cruelty. By a singular configuration of his own body he contrives to lodge his companions, one by one, upon his back, and then scrambling up the sides of the nest, he suddenly throws them from their seat, and completely ejects them from their own home to become food for worms. There is reason to believe that the unnatural parent is often an unmoved witness of this atrocity. Her whole care and affection are absorbed by the intruder, and her own flesh and blood literally turned out to perish. It sometimes, though very rarely, happens that two cuckoo's eggs are deposited in the same nest. When this occurs, and they are both hatched together, a bitter feud arises, which is only terminated by the ejection of one or other from the nest."

All naturalists previous to Jenner were inclined to ascribe the peculiarity in the economy of the cuckoo to its structure; the largeness of the stomach, which is only protected by a thin covering, they asserted, rendered the pressure attendant upon incubation incompatible with health. This theory is incorrect, and was adopted without due examination.

Jenner observes, "May they not, be owing to the following circumstances?--namely, the short residence this bird is allowed to make in this country, where it is destined to propagate its species, and the call that nature has upon it, during that short residence, to produce a numerous progeny. The cuckoo's first appearance here is about the middle of April. Its egg is not ready for incubation till some weeks after its arrival. A fortnight is taken up by the sitting bird in hatching the egg. The young bird generally continues three weeks in the nest before it flies, and the foster-parents feed it more than five weeks after this period: so that even if a cuckoo should be ready with an egg much sooner than the time pointed out, not a single nestling, would be fit to provide for itself, before its parent would be instinctively directed to seek a new residence, and be thus compelled to abandon its young; for the old cuckoos take their final leave of this country the first week in July."

The domestic incidents of Jenner's life during this period, although important to himself and his future career, were not otherwise remarkable. Having experienced a disappointment in his affections early in life, he continued for many years unmarried. Ultimately, however, on the 6th of March, 1788, he was married to Catherine Kingscote, a descendant of an ancient Gloucestershire family.

In 1793 John Hunter died, and Jenner was deeply affected by the loss of his esteemed friend. Many years previous to this sad event, Jenner's anxious and affectionate attention to the symptoms of the disease, which as early as 1777 had begun to attack Hunter, had enabled him to detect the true nature of his illness (Angina pectoris), and the result of the examination after death fully established the correctness of Jenner's views.

In 1792, having determined to give up the general practice of his profession, and practice as a physician only, Jenner obtained the degree of Doctor of Medicine from St. Andrews; and three years afterwards, on finding that Berkeley by itself could never support a physician, commenced making professional visits to Cheltenham, a practice which he continued for many years.

We now come to the important epoch in the life of this eminent man. On the 14th of May, 1796 (commemorated in Berlin as an annual festival), he made his first successful vaccination on a boy of the name of Phipps, eight years old, and announced the event in a letter to a friend named Gardner, in the following words: "But listen to the most delightful part of my story. The boy has since been inoculated for the small-pox, which, as I ventured to predict, produced no effect. I shall now pursue my experiments with redoubled ardour." In the year 1798 he made public the result of his continued observations and experiments, published during this year his work entitled an 'Inquiry into the Causes and Effects of the Variolæ Vaccinæ,' and henceforth the imperishable name of Jenner was to be identified with vaccination. Although Jenner announced his discovery thus late in life, his attention had been drawn forcibly towards the subject when quite a youth, while pursuing his professional education in the house of his master at Sudbury. During that time, a young countrywoman having come to seek advice, the subject of small-pox was mentioned in her presence; she immediately observed, "I cannot take that, for I have had the cow-pox." This incident rivetted the attention of Jenner, and he resolved to let no opportunity escape of procuring knowledge upon so interesting a subject. When, in 1770, he was prosecuting his studies in London, he mentioned the matter to Hunter, who told him not to _think_ but _try_, and above all to be patient and accurate. Hunter, however, from the great number of original and important pursuits, which fully engrossed his attention, was never so greatly impressed, as Jenner, with the probable consequences of the successful elucidation of the subject of cow-pox; while other surgeons and scientific men, to whom the subject was mentioned, ridiculed the idea; and even when Jenner had drawn up his 'Inquiry,' he was recommended not to send it to the Royal Society, lest it should injure the scientific reputation which he had formerly acquired with that body by his paper on the 'Natural History of the Cuckoo.' Undeterred by this want of sympathy, Jenner, during the time of his practice at Berkeley, patiently continued his investigations as to the nature of cow-pox, and, gradually struggling through the difficulties which he had to encounter on his way, eliminated the following facts: that there were certain people to whom it was impossible to give the small-pox by inoculation, and that these had all had the cow-pox; but that there were also others who had had cow-pox, and who yet received small-pox. This, after much labour, led him to the discovery that the cow was subject to a variety of eruptions, of which one only had the power of guarding from small-pox, and that this, the true cow-pox, as he called it, could, at only one period of its course, produce, by inoculation, such an influence upon the constitution as to render the individual safe from further contagion. This was the basis upon which the fundamental rules for the practice of vaccination were founded. The publication of his 'Inquiry' excited the greatest interest, for the evidence in it seemed conclusive; yet the practice of vaccination met with opposition, as severe as it was unfair, and its success seemed uncertain until a year had passed, when upwards of seventy of the principal physicians and surgeons in London signed a declaration of their entire confidence in it. An attempt was then made to deprive Jenner of the merit of his discovery, but it signally failed, and scientific honours began to be bestowed on him from all quarters. Nothing could, however, induce Jenner to leave his native village, and all his correspondence shows that the purest benevolence, rather than ambition, had been the motive which actuated his labours. In a letter to Mr. Clive, who instituted the first successful case of vaccination in London, he says: "Shall I, who, even in the morning of my life, sought the lowly and sequestered paths of life, the valley and not the mountain; shall I, now my evening is fast approaching, hold myself up as an object for fortune and for fame? Admitting it as a certainty that I obtain both, what stock should I add to my little fund of happiness? And as for fame, what is it?--a gilded butt for ever pierced with the arrows of malignancy." On the Continent Jenner's claims on the gratitude of mankind were quickly recognised, and the influence of his name and character was very great. On one occasion during the war he addressed a letter to Napoleon, requesting permission for two men of science and literature to return to England; and it is related that Napoleon, being about to reject the petition, heard Josephine utter the name of Jenner; on which the Emperor paused for an instant, and exclaimed, "Jenner! ah, we can refuse nothing to that man." He subsequently made other applications both to the French and other governments, which were uniformly attended with similar success. In fact his name became at length so potent, and his influence so well known, that persons left England with certificates signed by him, which had all the force and value of real passports. England, however, was more tardy in recognizing the claims of this great man. He once or twice applied to the British government on behalf of some French prisoners, but unhappily without success. Nor was he permitted to share in the least degree in the vast patronage at the disposal of the government, and all his attempts to obtain a living for one of his nephews failed, although he applied where he was quite justified in thinking he would meet with attention and success. On the occasion of the first parliamentary grant to Jenner in the year 1802, the Chancellor of the Exchequer stated that he thought the "approbation" of the House was the highest reward that could be given him, inasmuch as it would lead to an extended and very lucrative practice; and although it was proved in evidence that 40,000 men were annually preserved to the State, even at that time, by Dr. Jenner's discovery, the proposition of a grant for 10,000_l._ was carried only by a majority of three. Jenner's feelings were deeply wounded by the manner in which this grant was made, and he would gladly have repudiated the whole affair. It remained unpaid for two years, and when at length the money was paid to him, it was so loaded with taxes and other expenses, as to be of little pecuniary benefit. Happily, however, both for Jenner and the credit of Great Britain, the Marquis of Lansdowne (then Lord Henry Petty) was a principal mover in his second parliamentary grant, and through the able advocacy of this enlightened nobleman, together with Mr. Whitbread, Mr. Windham, and Mr. Edward Morris and others, a more fitting recompense of 20,000_l._, free of all charges, was awarded him in July 1807.

Jenner had several attacks of severe illness during his life, but he notwithstanding attained to a good old age. Till the last day of his life he was occupied in the most anxious labours to diffuse the advantages of his discovery both at home and abroad; and he had the satisfaction of knowing that vaccination had even then shed its blessing over every civilised nation of the world, prolonging life, and preventing the ravages of one of the most terrible scourges to which the human race was ever subject. He died suddenly from an attack of paralysis in July 1823, having attained the seventy-fifth year of his age.

Shortly after Jenner's death a statue was erected to his memory in Gloucester Cathedral, chiefly through the exertions of his friend and biographer, Dr. Baron; still more recently the statue in bronze, by William Calder Marshall, R.A., was erected in Trafalgar Square, and afterwards removed to Kensington Gardens, as a 'TRIBUTE FROM ALL NATIONS' to the memory of this distinguished philanthropist.--_Life of Edward Jenner, by John Baron, M.D., &c._ London, 1827.--_Memoir by Dr. Thos. Laycock, Encyclopædia Britannica._

WILLIAM JESSOP.

Born 1745. Died 1814.

This engineer forms the connecting link between the first and second generations of civil engineers in this country. To the former belong Smeaton and Brindley, while the latter are headed by the great names of Telford and Rennie.

The father of Mr. Jessop was engaged under Smeaton in superintending the erection of the Eddystone Lighthouse, and his son William, the subject of this memoir, was born at Plymouth. When he had attained the age of sixteen his father died, leaving the guardianship of his family to Smeaton, who thenceforth adopted William as his pupil, determining to bring him up to his own profession. Young Jessop remained with Smeaton for a period of ten years, enjoying, during this the busiest part of Smeaton's active career, many opportunities of acquiring an extensive knowledge of the business of civil engineering. After leaving the service of Smeaton, Mr. Jessop was engaged for several years in improving the navigation of the rivers Aire and Calder, and of the Calder and Hebble in Yorkshire. He was also employed on the river Trent in Nottinghamshire, and he appears to have been principally occupied on these works for some time subsequent to his leaving Smeaton.

A few years before the retirement of the latter, which took place in 1791, his pupil began to obtain active employment, and we find him about the years 1788 and 1789, reporting on the navigation of the Sussex Ouse, and the drainage of Laughton Level in the same country, being called on, at the same time, by the Commissioners of the Thames and Isis, to advise on the works they had undertaken, and were about to execute, for the improvement of this important navigation.

In the three following years (1790-2) his professional employment greatly increased. He was now actively engaged in prosecuting various important canals in connection with the great central navigation of the Trent. Amongst these were the Cromford Canal, penetrating amongst the mountains of Derbyshire into the rich mineral districts of that wild and romantic country; the Nottingham Canal, which connects the Cromford with the Trent at Nottingham; the Loughborough and Leicester navigation, connecting the Ashby Coalfield with the navigable part of the Soar and with Nottingham, thus opening an important communication with the Trent on the one hand, and with Nottingham and the whole south of England on the other. In addition to this system in connection with the Trent, he projected and commenced at this time the Horncastle navigation, which, besides acting as a valuable drainage for this part of the fens, was productive of great benefit to a large district, by bringing it into communication with the river Witham, which is navigable to the sea in one direction, and in the other through Lincoln to the Trent.

But a larger and more important work than these last named, which Mr. Jessop was at this period engaged on, was the Grand Junction Canal, which, joining the Oxford Canal at Braunston, in Northamptonshire, connects the whole inland navigation with the metropolis, by means of a comparatively direct line ninety miles in length, traced in a diagonal direction across the two formidable ranges of hills peculiar to the secondary formations of England.

This canal communicates with the Thames by its main line at Brentford, and by a branch starting five miles above at Bullbridge, stretching to Paddington, from whence the Regent's Canal proceeds round the north side of London to the Thames at Limehouse, thus completing the connection between the main line and the lower part of the river. The execution of this canal necessitated the construction of many heavy works, consisting of tunnels, deep cuttings, embankments, aqueducts, reservoirs, and weirs. Of these works one of the most famous is the Blisworth Tunnel, 3080 yards in length, cut through the inferior oolite and the shales of the lias. Its internal width is 16½ feet, the depth below the water-line to the inverted arch being 7 feet, while the soffit or crown of the arch is 11 feet above the same line. The cost of this great undertaking, with all its branches and attendant works, amounted to about two millions sterling.

During the execution of this work, Mr. Jessop was also called into Ireland, and was taking an active part in carrying on the public works which had been undertaken by the authority of Parliament in that country.

The year 1793 originated several great projects, in furtherance of which Mr. Jessop's aid was secured. Amongst these were the Grantham Canal, supplied by vast artificial reservoirs, and extending from the river Trent, through a rich pasture district of the new red sandstone, winding for many miles through the broad and fertile vale of Belvoir, up to Grantham at the base of the Lincolnshire hills, the furthest point to which it is possible to penetrate in this direction.

The Barnsley Canal, which opens up an immense amount of mineral wealth in the Yorkshire coalfield, and brings it into communication with the river Calder, and the Dearn and Dove Canal; and finally, the Great Ellesmere Canal, which completes a communication between the Severn and the Mersey, and ramifies in numerous directions amongst the rugged hills and valleys of North Wales.

In the carrying on of this last named undertaking, Mr. Telford was likewise engaged under Mr. Jessop. Two of its most important works are the great aqueducts of Chirk and Pont-y-cysylte, the former of which carries the canal over the river Ceriog, at an elevation of 70 feet, while the latter carries it across the Dee at an elevation of 127 feet. The grand peculiarity in these aqueducts consisted in constructing a water-tight trough of cast iron for carrying the canal across the arches, instead of an immense puddled clay trough, as was the practice until that time in use. The execution and management of the numerous works here mentioned occupied the greater part of Mr. Jessop's time during the next few years. But the commencement of the present century was the signal for another torrent of speculation, which, in addition to canals, began now to be directed towards docks and railroads. The promoters of the first great public dock establishment employed Mr. Jessop to conduct their works, and he had the honour of completing the great project of the West India Docks, with their numerous accompanying details, in a manner which alone entitles him to rank among our most eminent engineers.

On the completion of these docks his professional services were engaged by the citizens of Bristol, to effect a great and comprehensive measure of harbour improvement, designed to place the port of Bristol at once in the foremost position with respect to commercial advantages. This was the conversion of part of the river Avon into an immense floating dock, capable of accommodating 1400 vessels. Mr. Jessop was also at this time occupied in constructing the Surrey iron railways, which consisted of a double tramroad, from the Thames at Wandsworth to the town of Croydon, with an extension from Croydon to Godstone and Merstham; they are principally remarkable as being the first public railroads constructed in the south of England. The whole of these tramroads were afterwards bought and taken up by the Brighton Railway Company. Mr. Jessop was likewise connected with the Caledonian Canal, which he was specially called upon to survey before its commencement, and of which he continued to be the consulting engineer for many years.

In concluding this brief notice of Mr. Jessop's life, it remains only to be said that with him exclusively originated the idea of taking advantage of the immense floods to which certain districts are subject, by storing these waters up for the gradual and regular supply of his canals. In addition to this he shares with Mr. Telford the honour of first using iron in the construction of the troughs of aqueducts, and for the heads, heel-posts and ribs of lock-gates, as adopted on the Caledonian and Ellesmere canals.--_Memoir of William Jessop, by Samuel Hughes, C.E._

CAPTAIN HENRY KATER, F.R.S., &c.

Born April 16, 1777. Died April 26, 1835.

Captain Henry Kater, distinguished by his mathematical and physical researches during the space of nearly half a century, was born at Bristol; his father was of a German family, and his mother was the daughter of an eminent architect; both were distinguished for their scientific attainments, and united in imbuing their son with a similar taste. Henry was, however, destined by his father for the law, and had with great reluctance to give up for a time his hitherto exclusive devotion to abstract science. Mr. Kater continued for two years to remain in a pleader's office, during which time he acquired a considerable portion of legal knowledge, on which he valued himself through life; but the death of his father, in 1794, permitted him to resume his favourite studies; and bidding adieu to the law, he obtained a commission in the 12th Regiment of Foot, at that time stationed in India.

During the following year, Mr. Kater was engaged in the trigonometrical survey of India under Colonel Lambton, contributing greatly, by his untiring labours, to the success of that vast undertaking. About the same period, he was also occupied in constructing a peculiarly sensible hygrometer, of which he published a description in the 'Asiatic Researches.' Mr. Kater remained in India seven years, during which time his unremitting study in a hot climate greatly injured his constitution, and was the cause of his falling into a state of ill health, from which he suffered more or less until the end of his life.