forming a communication between the tidal river Linge and
the canal of Steenenhock. The arrangement resembles
that of the above diagram, the chamber of the lock being
in the place of B, and its other end being closed by a pair
of common gates opening towards the river.
SLUR, in Music, a curved line
more or less ex-
tended, as may be required, drawn over two or many notes.
If placed over two notes on the same line or space, it signi-
fies that the second is not to be repeated, though to be held
out its due time. When drawn over notes on different de-
grees, it signifies that they are to be legato, i.e. tied-played
in a smooth blending manner. This character is some-
times called a bind, and also a tie.

SLUYS (in French, L'Ecluse), is a very strongly fortified town in the province of Zealand, in the kingdom of the Netherlands. It is situated in 53° 18′ 30′′ N. lat. and 3° 20′ E. long., on a small bay of the German Ocean called the Zwin, at the mouth of the Schelde, and is connected by a canal with the city of Bruges, which is about 15 miles distant. The harbour, which was formerly deep and clean, is not now capable of admitting any but small vessels. It is furnished with sluices (whence its name), by which, in case of a siege, all the surrounding country can be laid under water. It has about 1400 inhabitants. It was taken by the French in 1794.

SMÄLAND. [SWEDEN.]

and children often die of suffocation from this cause; the extent of mucous and of cutaneous inflammation however are not always necessarily proportioned to each other Small-pox rarely attacks the same individual more than once, and, like measles and scarlatina, its consequences are sometimes more to be dreaded than the disease itself. During the secondary fever, an intense form of ophthalmia frequently sets in, which rapidly involves all the structures of the eye, and in the course of a few days destroys its entire organization. Although it is not common to have both eyes thus affected, still a large proportion of the blind at our public institutions owe their misfortune to this disease. Pleurisy, consumption, scrofula, obstinate diarrhoea, and a fetid discharge from the ears attended with more or less deafness, are the principal diseases liable to result from a severe attack of small-pox. The immediate cause of this disease is a peculiar miasm or poison received into the system from an individual labouring under the same affection, and it is said to make its appearance in from twelve to fourteen days after exposure to the contagion; when however it is communicated by inoculation, it appears on the seventh or eighth day. Instances are recorded of mothers who were exposed to the infection of small-pox, communicating the disease to the foetus in utero, without being themselves affected by it; and, what is equally remarkable, women suffering from small-pox during pregnancy, have brought forth healthy children, who did not take the disease till they were inoculated. Small-pox is frequently epidemic, especially in the spring, and, like all other epidemics, those who are first attacked by it suffer the most severely it is observed also to be greatly influenced by certain conditions of the atmosphere.

it in its originating from the 'variolous germ,' and in its power of communicating the true small-pox to others, as well by inoculation as by infection.

SMALL-POX (Variola). It is a subject of dispute whether this disease was known to the antients, or whether it has originated at a comparatively recent date. Those who contend for its antiquity refer us to the account of the plague of Athens by Thucydides (ii. 46, &c.), which, they say, is as accurate a description of the leading symptoms of Variola as could possibly be expected from any historian Small-pox can be communicated by inoculation with who is not a physician. Those who hold the opposite the matter of its pustules, and the resulting disease being opinion call in etymology to their aid; the word pock or rendered milder by this operation, it was formerly much por, they say, is of Saxon origin, and signifies a bag or practised to guard the individual against a spontaneous pouch; the epithet small in England, and petite in France, attack; since however the introduction of vaccination were added in the fifteenth century. The term variola is by Dr. Jenner, the practice has been deservedly abanderived from the Latin word varus, a pimple, or varius, doned. Vaccination was supposed by its discoverer to spotted; and, according to Moore, the first authentic pas- secure the individual permanently and effectually from the sage in which it occurs is to be found in the Bertinian contagion of the small-pox; more extended experience has Chronicle' of the date 961. The first author however who proved, that although it does not always prevent it, yet it so treats expressly of small-pox is Rhazes, an Arabian phy- shortens its duration and moderates its violence, that a sician [RHAZES], but even he confounded it with measles, death from small-pox after vaccination is a rare occurrence. and these two diseases continued to be considered as modi- A difference of opinion prevails respecting the character of fications of the same disorder till the time of Sydenham. the eruption which occasionally appears after exposure to Small-pox, when it occurs naturally, is preceded by the variolous infection in persons previously vaccinated. Acusual premonitory symptoms of eruptive fevers, such as cording to many, it is nothing more than chicken-pox; while rigors, pains in the back and loins, prostration of strength, others affirm that it is really small-pox, although modified loss of appetite, nausea, and sometimes vomiting, and, in by the controlling influence of the cow-pox. The truth young children, frequently convulsions. About forty-eight appears to be, that modified small-pox resembles the hours after the commencement of these symptoms an erup-chicken-pox in its mildness and duration, but differs from tion of small, hard, red-coloured pimples makes its appearance about the face and neck, and gradually extends downwards over the trunk and extremities. The primary fever, as it is called, now lessens; but the pimples increase in size, and become converted into whey coloured pustules with a depression in their centre. On the eighth day they are at their height, and on the eleventh the matter oozes from them and concretes into crusts, which fall off about the fourteenth day, leaving the skin of a brownish-red colour, and studded with slight depressions or pits. As the eruption travels from above downwards, the parts of the body successively attacked by it become affected with swelling, the mouth waters, and the voice is hoarse; when the incrustation has taken place, these symptoms subside, but a secondary fever commences, which is sometimes more severe than that which preceded the outbreak of the eruption. Small pox, according to its severity, is distinguished by authors into two varieties, the distinct and the confluent, variola discreta and confluens. In the former, the pustules are few in number, well formed, and do not touch each other, and the fever is inflammatory, but mild; in the latter, the disease altogether is more violent, the eruption more general, and the pustules, small and unhealthy, run one into another. The fever likewise is greater, and rather of the typhoid character, is not mitigated on the appearance of the eruption, and is much aggravated at its termination; there is delirium, considerable prostration of the vital powers, ptyalism, inflammation of the fauces, and frequently diarrhoea. Petechiæ and an unhealthy exudation from the body often accompany this form of the disease. Among the mucous membranes, the larynx and trachea suffer much,

The history of the different epidemics of small-pox shows the mortality to be one in four of those attacked who had not been vaccinated; whilst of those who had undergone vaccination the proportion was not one in 450. From the register kept at the Small-pox Hospital in London, it appears that the mortality at this institution is considerably greater than one in four, having averaged during the last fifty years 30 per cent,, the extremes being 18 and 41. From the same source we learn that the greatest number of deaths occurs on the eighth day. Of 168 fatal cases, there died in the first week 32; in the second, 99; in the third, 21; and in the fourth and after, 16. The causes of death at these different periods are the following:-1st week, malignant fever; 2nd week, affections of the throat, and consequent suffocation; 3rd week, or during the secondary fever, febrile excitement, mortification of large portions of the integuments, pneumonia, pleurisy, or laryngitis; 4th and following weeks, exhaustion, erysipelas, or some of the diseases before enumerated as liable to result from small-pox. It was formerly supposed that the eruption of variola was not confined to the skin, but invaded also the internal parts; this is not the case, the internal affections are simply inflammatory, and do not partake of the specific character of the cutaneous disease.

No peculiar plan of treatment is required for small-pox; it is that of ordinary fever: cleanliness, free ventilation, an attention to the strength of the patient, and a watchfulness against accidental complications, are the principal points to

dotted. All the species are upright shrubs, with white, showy, axillary flowers. Three species are recorded, & pubescens, S. lævigata, and S. media. In cultivation they succeed best in a mixture of loam, peat, and sand. They may be easily propagated by sticking cuttings in the same soil under a bell-glass.

be kept in view. During the eruptive stage of the disorder, | capsule is inflated, and four- or five-valved; the seeds are the bowels should be kept moderately open by saline aperients, and the occasional exhibition of a mild mercurial. The temperature of the skin may be regulated by cool air, or by sponging it with tepid vinegar and water; if there should be much unpleasant effluvium from the surface of the body, washing it with a weak solution of one of the chlorides will be found to correct this. It has been recom- SMEATON, JOHN, was born, according to most mended by some writers, and has been long a practice in authorities, on the 28th of May, 1724, as Austhorpe, near Eastern countries, to pierce the pustules with a fine needle; Leeds, in a house built by his grandfather, and long afterthis procedure, it is said, lessens the violence of the second-wards inhabited by his family. His father was an attorney, ary fever, and prevents pitting. M. Serres, with the same and brought him up with a view to the legal profession. object, directs the application of lunar caustic to the pus- Our information respecting the domestic history of Smeaton tules on the fourth day. As a general rule, we should say is exceedingly scanty; it amounts to little more than that be that venesection is not admissible at any period of small- very early displayed a taste for mechanical pursuits; delightpox; indeed we have no hesitation in affirming that some ing, it is said, even when a child in petticoats, to observe of the severest consequences of the disease may be averted mechanics at work, and to question them respecting their by a judicious employment of measures of an opposite employments. One of his biographers states that his toys tendency to blood-letting. The sloughing of the integu- were the tools of men; and that, while yet little more than ments, and the intense ophthalmia, rapidly terminating in an infant, he was discovered one day on the top of his entire loss of vision, are eminently connected with an en- father's barn, fixing something like a windmill. But passfeebled and cachectic state of body; and the best mode of ing over such symptoms of precocity, the evidence of which averting these evils is to have recourse early to those reme- must always be received with caution, we find him, at the dies which are most efficacious in arresting their progress. age of fourteen or fifteen, constructing a machine for roseHence bark or its preparations, combined with the mineral engine turning, and producing neat ornamental boxes, &c. for acids, sarsaparilla, wine, brandy, if the powers are much his friends. He appears to have been but little older when reduced, and animal food, if the patient can eat it, must be he cut, in a lathe of his own manufacture, a perpetual screw perseveringly administered. It may not be out of place in brass, according to the design of his intimate friend Mr. here to mention that the character of the ophthalmia termed Henry Hindley of York, with whom he joined enthusiastically variolous has only lately been pointed out to the profession in mechanical pursuits. By the age of eighteen years he had by Mr. Marson of the Small-pox Hospital. It had been sup- attained much practical skill in mechanical operations, and posed that the eye was lost in small pox from one or more had furnished himself with many tools for performing them. of the pustules of this disease forming on the cornea. Mr. About this time, in the year 1742, in pursuance of his Marson has shown not only that this never takes place, father's design, young Smeaton came to London, and atbut that the loss of vision is attributable to ulceration or tended the courts of law at Westminster Hall; but finding sloughing of the cornea, which comes on generally about the bent of his mind averse to the law, his father yielded to the eleventh or twelfth day of the disease. The patient is his wishes, and allowed him to devote his energies to more nearly always in a state of great debility, and requires tonic congenial matters. The next circumstance in his history medicines and nutritious diet to give him a chance of related by his very brief biographers is his taking up the escaping from the destructive effects of this ophthalmia. business of a mathematical-instrument maker, about the year 1750, when he was residing in lodgings in Great Turnstile, Holborn. In 1751 he tried experiments with a machine that he had invented for measuring a ship's way at sea; and in 1752 and 1753 was engaged in a course of experiments concerning the natural powers of water and wind to turn mills and other machines depending on circular motion. From the latter investigation resulted the most valuable improvements in hydraulic machinery. In the construction of mill-work, Smeaton, during the whole of his useful career as a civil engineer, stood deservedly high; and, by his judicious application of scientific principles, he increased the power of machinery impelled by wind and water as much as one-third. The results of these experiments were published in 1759, after he had been able to give them a practical trial; and their value obtained for him the Copley gold medal of the Royal Society in that year. Smeaton had previously, in the year 1753, been made a member of the Royal Society; and he had made some communications to the Transactions' even before that date. In 1754 he visited Holland and the Netherlands; and the sequaintance he thus obtained with the construction of embankments, artificial navigations, and similar works, probably formed an important part of his engineering education.

SMALT is a glass coloured of a fine blue, by means of oxide of cobalt. [COBALT.] When reduced to an impalpable powder, it is employed to give a blue tint to writingpaper and linen.

SMART, CHRISTOPHER, was born at Shepburne in Kent, April 11, 1722. He was educated at Durham and Maidstone schools, and at Pembroke Hall, Cambridge, where he was sent October 30, 1739. Here he distinguished himself by his classical attainments; he was elected a fellow of Pembroke Hall, July 3, 1745. He gained the Seatonian prize for five successive years: the subjects of the prize poems were respectively the Eternity, the Immensity, the Omniscience, the Power, and the Goodness of the Supreme Being. In 1753 he quitted Cambridge on his marriage with Miss Ann Maria Carman, and afterwards resided in London, endeavouring to make a livelihood by trifling literary undertakings. He became engaged in an altercation with Sir John Hill, who criticised his poems, and Smart in revenge published a satire called the 'Hilliad.'

In 1754, in consequence of pecuniary embarrassment and other mortifications, he became deranged, and continued in this condition, with intervals more or less lasting of sanity, till his death, May 18, 1770, in the rules of the King's Bench, where he had been confined in his latter years. Smart translated the Psalms, Phædrus, and Horace into prose; and in 1752 published a small collection of poems, to which he made subsequent additions. His productions have sunk into deserved oblivion. He seems to have been a weak improvident man, not destitute of good qualities, such as gained the favour of several of the nobility, and the friendship of Garrick and Johnson, the latter of whom has written an account of him. His poems were printed in 1791.

SMEATHMA'NNIA, a small but beautiful genus of plants belonging to the natural order Passifloracea. It was named by Solander in honour of Smeathmann, a German botanist, who travelled in many parts of Western Africa, and collected plants, especially at Sierra Leone, of which place this genus is exclusively a native. The genus possesses a one-leaved nectarium, which is urceolate and surrounding the base of the stamens. The stamens are numerous, distinct, and seated on a short column with incumbent anthers; the stigmas are peltate and five in number; the

In 1766 Smeaton commenced the great work which, more than any other, may be looked upon as a lasting monument of his skill-the EDDYSTONE LIGHTHOUSE [ix. pp. 268, 269]. Two lighthouses had been erected on the Eddystone or Edystone rock, before the admirable strueture of Smeaton; of which the first was swept away in a storm, and the second, which was formed of timber, was destroyed by fire in December, 1755. The immediate reerection of the beacon being highly important, Mr. Weston, the chief proprietor, lost no time in applying to the earl of Macclesfield, then president of the Royal Society, for ad vice as to the person who should be entrusted with the difficult task. The previous structures had been designed by non-professional men; and it was felt now, to adopt the language of Smeaton's narrative, that to erect another would not so much require a person who had merely been bred or had even rendered himself eminent in this or that

planation is offered of this deviation from, as far as the writer can ascertais, June 18th is the date given in the Eucyclopædia Britannica; but no exall other authorities,

given profession; but rather one who from natural genius had a turn for contrivance in the mechanical branches of science.' The earl immediately perceived that Smeaton was the man required, and therefore recommended him. Although a great portion of the lease under the provisions of which the lighthouse had been erected was expired, and their interest in the undertaking was consequently limited to a comparatively short time, the proprietors liberally entered into Smeaton's views respecting the superior advantages of a more durable material than timber; and determined on the adoption of his plans for a stone structure of the greatest possible strength. The cutting of the rock for the foundation of the building was commenced on the 5th of August, 1756; the first stone was landed upon the rock June 12th, 1757; the building was finished on the 9th of October, 1759, and the lantern lighted for the first time on the 16th. During this time there were 421 days' work done upon the rock.

Smeaton appears to have been by no means fully employed as an engineer for several years after the completion of the Eddystone lighthouse; for in 1764 he became a candidate for the office of a receiver of the Derwentwater estate, the funds of which were, after its forfeiture in 1715, appropriated to Greenwich Hospital. On the last day of that year, chiefly, as he states in his account of the Eddystone lighthouse, through the friendship of the earl of Egmont and earl Howe, lords of the admiralty, he was appointed to this office. In this engagement he was happy in being associated with Mr. Walton, the other receiver, who took upon himself the management of the accounts, leaving Smeaton at leisure to devote his attention to improvements and to professional engagements. While he held the receivership he greatly improved the estate, the mines and mills of which required the superintendence of such a man to make them of their full value. Increasing business induced him, in 1775, to desire to relinquish this engagement, but he was prevailed on to retain it about two years longer.

Of the many useful works executed by Smeaton, Ramsgate harbour perhaps holds, next to the Eddystone lighthouse, the most prominent place. This work was commenced in 1749, but was carried on with very imperfect success until it was placed under his superintendence in 1774. This harbour, being enclosed by two piers, of about 2000 and 1500 feet long respectively, affords a safe refuge for ships where it was much needed, vessels in the Downs having been exposed to imminent risk during bad weather before it was constructed. Smeaton laid out the line of the great canal connecting the western and eastern shores of Scotland, from the Forth to the Clyde, and superintended the execution of great part of it. To his skill, in all probability, the preservation of old London bridge for many years was attributable. In 1761, in consequence of alterations made for the improvement of the navigation, one of the piers was undermined by the stream to a fearful extent. The bridge was considered in such danger that no one would venture to pass over it; and the engineers were perplexed. An express was therefore sent to Yorkshire for Smeaton, who immediately sunk a great quantity of stones about the endangered pier, and thereby preserved it. The Calder navigation was one of the great works which he successfully accomplished; and he provided with much skill for the effect of the impetuous floods to which that river is subject. The Spurn lighthouse at the mouth of the Humber, some important bridges in Scotland, and many other works of like character might also be mentioned.

About 1783 Smeaton's declining health rendered it necessary for him to avoid entering upon many new undertakings. He then devoted much attention to the publication of an account of the Eddystone lighthouse, which was to have been followed by a Treatise on Mills,' and other works embodying his valuable experience as an engineer. The former of these was the only work he lived to complete; and it is a volume of great and permanent interest, detailing in the most minute and simple manner every circumstance worthy of record concerning the history or the construction of the lighthouse. It is dedicated to George III., who had taken much interest in the structure; and in the dedication, in explaining the circumstances which had deferred the appearance of the narrative so long after the completion of the building, the author observes, I can with truth say, I have ever since been employed in works tending to the immediate benefit of your majesty's subjects; and P. C., No. 1377.

indeed so unremittingly, that it is not without the greatest exertion that I am enabled even now to complete the publication.' He had made some progress in this work before 1763; but it appears to have been laid aside for about twenty years, and was not published until 1791. On the 16th of September, 1792, while walking in his garden at Austhorpe, Smeaton was seized with an attack of paralysis; and on the 28th of October he died.

About the year 1771 several friends of Smeaton, engaged in kindred pursuits, formed themselves into a society, which may perhaps be looked upon as the first public recognition of the useful body of men who have since, under the name of Civil Engineers, done so much in developing the resources of this country. Untoward circumstances led to the dissolution of this society previous to Smeaton's death but steps were taken to re-organize.it before that event took place. The new Society shortly took steps for the publica tion in a collected form of Smeaton's numerous professional reports; but the work was not completed until 1812. It is in three quarto volumes, to which a fourth was subsequently added, consisting of his miscellaneous papers communicated to the Royal Society, &c. The Society alluded to is mentioned in the first volume of the Transactions of the Institution of Civil Engineers' as still existing. The introduction to this volume contains a high eulogium on the talent of Smeaton as an engineer. Alluding to the Eddystone lighthouse, it observes, This, Smeaton's first work, was also his greatest; probably, the time and all things considered, it was the most arduous undertaking that has fallen to any engineer, and none was ever more successfully executed. And now, having been buffeted by the storms of nearly (now more than) eighty years, the Eddystone stands unmoved as the rock it is built on a proud monument to its great author. Buildings of the same kind have been executed since, but it should always be borne in mind who taught the first great lesson, and recorded the progressive steps with a modesty and simplicity that may well be held up as models for similar writings. His Reports are entitled to equal praise; they are a mine of wealth for the sound principles which they unfold and the able practice they exemplify, both alike based on close observation of the operations of nature, and affording many fine examples of cautious sagacity in applying the instructions she gives to the means within the reach of art.' The deliberation and caution always exercised in the works of Smeaton are well worthy of imitation; and to this may be attributed the almost unexampled success of his undertakings. So highly was his judgment appreciated, that he has been called the standing counsel' of his profession, and he was constantly appealed to by parliament on difficult engineering questions. His improvements of wind and water mills have been mentioned already. The atmospheric steam-engine of Newcomen was the subject of similar experiments, attended with the like results; although the more important improvements of Watt threw Smeaton's efforts in this way comparatively into the shade. His improvements consisted chiefly in the proportions of the component parts of the machine; yet they effected so great a saving of fuel, that Boulton and Watt excluded them from their ordinary agreement-which was, to receive for the use of their patent right one-third of the coal saved by their machine in comparison with those previously used. The low state of the mechanic arts in England led Smeaton, during the early part of Watt's career, to doubt the possibility of his machines being made with the required accuracy.

Smeaton also introduced many improvements in mathematical apparatus, and had an ardent love for science. He was particularly attached to astronomy, and had an observatory at Austhorpe, where, even during the most active part of his career, he occasionally resided.

In person he was of middle stature, broad and strong made, and of good constitution. His manners were simple and unassuming. His temper was warm, but not overbearing; and his social character unimpeachable. Very little is recorded of his private history; but his daughter, Mary Dixon, in a letter prefixed to his Reports,' gives a pleasing account of his character as a husband, parent, and friend He was by no means grasping or avaricious, as many anecdotes related of him seem to show. The empress Catharine of Russia was at one time very desirous of engaging his services, and offered him his own terms: but the princess Daschkaw, by whom the request was communicated, found him to be, as she said, a man who had no price.

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