STEREOGRAPHIC projection, is the projection of the circles of the sphere on the plane of some one great circle, the eye being placed in the pole of that circle. STEREOGRAPHY, the art of drawing the forms and figures of the solids upon a plane.

STEREOMETRY, that part of geometry which teaches how to measure solid bodies, i. e. to find the solidity or solid content of bodies, as globes, cylinders, cubes, vessels, ships, &c.

STEREOTYPE printing. See PRINTING, stereotype. In the beginning of that article an error escaped our notice; for by the Jesuits," read "say the Jesuits." We take likewise this opportunity of adding to the article, that though there have unquestionably issued many beautiful specimens of printing from the stereotype press; yet, as the beauty of a book must depend, as well in the stereotype, as in moveable types, on the form and excellence of the letter, it is evident that the same letter from which the stereotype plate is cast, will, in common printing produce as beautiful a page: of this we could adduce many instances; but, perhaps, no person has sent from his office more specimens of this kind than the printer of this dictionary.

STERLING, a term frequent in British commerce. A pound, shilling, or penny, sterling, signifies as much as a pound, shilling, or penny, of lawful money of Great Britain, as settled by authority.

STERN of a ship, usually denotes all the hindermost part of her, but properly it is only the outmost part abaft.

STERN fast, denotes some fastenings of ropes, &c. behind the stern of a ship, to which a cable, or hawser, may be brought or fixed, in order to hold her stern to a wharf, &c.

STERN post, a great timber let into the keel at the stern of a ship, somewhat sloping, into which are fastened the afterplanks; and on this post, by its pintle and gudgeons, hangs the rudder.

STERNA, the tern, in natural history, a genus of birds of the order Anseres. Generic character: bill straight, pointed, and slender; nostrils linear; tongue slender and pointed; wings very long; back toe small; tail forked. There are twenty-five species. The following are the principal: S. caspia, or the Caspian tern; this abounds on the seas wherein it derives its name. It fishes also in rivers, and sometimes suddenly darts upon its prey from a considerable height, and at other times skims the surface of the water in the manner of a swallow. VOL. XI.

It is nearly two feet in length. It lays only two eggs, and its sound resembles that of a person laughing.

S. stolida, or the noddy, is a foot and a quarter long, and is frequently met with at sea, between the tropics. It lays its eggs on the bare ground; is considered by navigators as generally indicating the neighbourhood of land; often alights on the yards and rigging of vessels; will suffer itself to be taken by the hand; and from the general want of sagacity which it exhibits, is called by sailors by the name of noddy. It will, however, notwithstanding its alleged tameness and stupidity, often bite with great severity.

S. hirundo, the great tern, is found in various parts of Europe, and in summer on the British coasts. It is fourteen inches long. Its manners, on the water, resemble those of the swallow by land. It skims along precisely in the same manner, catching every insect in its progress; and when it perceives a fish, it darts into the water, and reverts to the air with a rapidity truly astonishing. It is bold and daring; and, in the season of incubation, will attack persons who have given it no molestation, and are at a distance from its nest. For the lesser tern, see Aves, Plate XIII. fig. 7.

STERNOPTYX, in natural history, a genus of fishes of the order Apodes. Generic character: head obtuse; mouth abrupt; teeth very small; no gill-membrane; body compressed, without visible scales; breast carinate, both ways folded, abdomen pellucid. The transparent sternoptyx, the only species under this genus, is between two and three inches long, and is found in the American Seas. Its back rises into a sharp edge. Its general colour is that of a bright silver; but on the back it is somewhat olive-coloured, and its fins and tail are of an obscure yellow; its tail is bifid. See Pisces, Plate VI. fig. 2.

STEW, a small kind of fish-pond, the peculiar office of which is to maintain fish, and keep them in readiness for the daily use of a family, &c. The fish bred in the large ponds are drawn out and put in here. For two large ponds, of three or four acres a-piece, it is advisable to have four stews, each two rods wide, and three long. The stews are usually in gardens, or at least near the house, to be more handy, and the better looked to. The method of making them is, to carry the bottom in a continued decline from one end, with a mouth to favour the drawing with a net.

STEWARD, an officer appointed in

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another's stead or place, and always taken for a principal officer within his jurisdic.

tion

Of these there are various kinds. The greatest officer under the crown is the Lord High Steward of England, an office that was anciently the inheritance of the Earls of Leicester, till forfeited, by Simon de Mountford, to King Henry III. But the power of this officer is so very great, that it has not been judged safe to trust it any longer in the hands of a subject, excepting only pro hac vice, occasionally: as, to officiate at a coronation, at the arraignment of a nobleman for high treason, or the like. During his office, the Steward bears a white staff in his hand, and the trial, &c ended, he breaks the staff, and with it his commission expires. There is likewise a Lord Steward of the King's household, who is the chief officer of the King's court, has the care of the King's house, and authority over all the officers and servants of the house. hold, except such as belong to the chapel, chamber, and stable.

There is also a steward of the Marshal sea, who has judicial authority. And in most corporations, and all houses of quality in the kingdom, there is an officer of the name and authority of a steward.

The steward of a ship is he who receives all the victuals from the purser, and is to see it well stowed in the hold; all things of that nature belonging to the ship's use are in his custody; he looks after the bread, and distributes out the several messes of victuals in the ship; he hath an apartment for himself in the hold, which is called the steward's room.

STEWART, (the Rev. Dr. MATTHEW,) in biography, late professor of mathematics in the University of Edinburgh, was the son of the Rev. Mr. Dugald Stewart, minister of Rothsay, in the Isle of Bute, and was born at that place in the year 1717. After having finished his course at the grammar school, being intended by his father for the church, he was sent to the University of Glasgow, and was entered there as a student in 1734. His academical studies were prosecuted with diligence and success; and he was so happy as to be particularly distinguished by the friendship of Dr. Hutcheson, and Dr. Simson, the celebrated geometrician, under whom he made great progress in that science.

Mr. Stewart's views made it necessary for him to attend the lectures in the University of Edinburgh, in 1741; and that his mathematical studies might suffer no interruption, he was introduced by Dr. Simson to Mr. Maclaurin, who was then

teaching both the geometry and the phi losophy of Newton, and under whom Mr. Stewart made that proficiency which was to be expected from the abilities of such a pupil, directed by those of so great a master. But the modern analysis, even when thus powerfully recommended, was not able to withdraw his attention from the relish of the ancient geometry, which he had imbibed under Dr. Simson. He still kept up a regular correspondence with this gentleman, giving him an ac count of his progress, and of his discoveries in geometry, which were now both numerous and important, and receiving in return many curious communications with respect to the Loci Plani, and the Porisms of Euclid. Mr. Stewart pursued this latter subject in a different and new direction. In doing so, he was led to the discovery of certain curious and interesting propositions which he published under the title of "General Theorems,” in 1746. They were given without the demonstrations; but they did not fail to place their discoverer at once among the geometricians of the first rank. They are, for the most part, Porisms, though Mr. Stewart, careful not to anticipate the discoveries of his friend, gave them only the name of Theorems. They are among the most beautiful, as well as most general propositions, known in the whole compass of geometry, and are perhaps only equalled by the remarkable locus to the circle in the second book of Apollonius, or by the celebrated theorem of Mr. Cotes.

In September, 1747, he was elected professor of mathematics in the University of Edinburgh. The duties of this office gave a turn somewhat different to his mathematical pursuits, and led him to think of the most simple and elegant means of explaining those difficult propositions, which were hitherto only accessible to men deeply versed in the modern analysis. In doing this, he was pursuing the object, which of all others, he most ardently wished to attain, viz. the application of geometry to such problems as the algebraic calculus alone had been thought able to resolve. His solution of Kepler's problem was the first specimen of this kind which he gave to the world. This is founded on a general property of curves, which, though very simple, had perhaps never been observed; and by a most ingenious application of that property, he shows how the approximation may be continued to any degree of accuracy, in a series of results which converge with great rapidity.

This solution appeared in the second volume of the Essays of the Philosophical Society of Edinburgh, for the year 1756. In the first volume of the same collection there are some other propositions of Mr. Stewart's, which are an extension of a curious theorem in the fourth book of Pappus. They have a relation to the subject of Porisms, and one of them forms the ninety-first of Dr. Simson's Restoration.

He next published the "Tracts, Physical and Mathematical." In the first of these, Mr. Stewart lays down the doctrine of centripetal forces, in a series of propositions, demonstrated (if we admit the quadrature of curves) with the utmost rigour, and requiring no previous knowledge of the mathematics, except the elements of plane geometry, and of conic sections. The good order of these propositions, added to the clearness and simplicity of the demonstrations, renders this tract perhaps the best elementary treatise of physical astronomy that is any where to be found.

In the three remaining tracts, our author had it in view to determine the effect of those forces which disturb the motions of a secondary planet. From this he proposed to deduce, not only a theory of the moon, but a determination of the sun's distance from the earth. The former, it is well known, is the most difficult subject to which mathematics have been applied, and the solution required and merited all the clearness and simplicity which our author possessed in so eminent a degree. It must be regretted, therefore, that the decline of Mr. Stewart's health, which began soon after the publication of the tracts, did not permit him to pursue this investigation. The other object of the tracts was, to determine the distance of the sun, from his effect in disturbing the motions of the moon; and his inquiries into the lunar irregularities had furnished him with the means of accomplishing it, as he supposed: and in 1763, he published his "Essay on the Sun's distsnce," where the computa tion being actually made, the parallax of the sun was found to be no more than 6" 9"", and consequently his distance almost 29,875 semi-diameters of the earth, or nearly 119 millions of miles. A determination of the sun's distance, that so far exceeded all former estimation of it, was received with surprise, and the reasoning on which it was founded was likely to undergo a severe examination. But, even among astronomers, it was not every one who could judge in a matter of such difficult discussion. Accordingly, it was not till above five years after the publication

of Dr. Stewart's work, that there appeared a pamphlet, under the title of "Four Propositions," intended to point out certain errors in Dr. Stewart's investigation, which had given a result much greater than the truth. From his desire of simplifying, and of employing only the geometrical method of reasoning, he was reduced to the necessity of rejecting quantities, which were considerable enough to have a great effect on the last result. An error was thus introduced, which, had it not been for certain compensations, would have become immediately obvious, by giving the sun's distance near three times as great as thatwhich has been mentioned.

The Sun's Distance" was the last work which Dr. Stewart published; and though he lived to see the animadversions made on it, he declined entering into any controversy. His disposition was far from polemical; and he knew the value of that quiet, which a literary man should rarely suffer his antagonists to interrupt. He used to say that the decision of the point in question was now before the public; that if his investigation was right, it would never be overturned; and that if it was wrong, it ought not to be defended.

A few months before he published the Essay just mentioned, he gave to the world another work, entitled, "Propositiones More Veterum Demonstratæ." It consists of a series of geometrical theorems, mostly new; investigated, first by an analysis, and afterwards synthetically demonstrated by an inversion of the same analysis. This method made an important part in the analysis of the ancient geometricians; but few examples of it have been preserved in their writings, and those in the "Propositiones Geometrica" are therefore the more valuable.

Doctor Stewart's constant use of the geometrical analysis had put him in possession of many valuable propositions, which did not enter into the plan of any of the works that have been enumerated. Of these, not a few have found a place in the writings of Dr. Simson, where they will for ever remain, to mark the friendship of these two mathematicians, and to evince the esteem which Dr. Simson entertained for the abilities of his pupil. Many of these are in the work upon the Porisms, and others in the Conic Sections, viz. marked with the letter a; also a theorem in the edition of Euclid's Data.

Soon after the publication of the "Sun's Distance," Dr. Stewart's health began to decline, and the duties of his office became burdensome to him. In the year 1772, he retired to the country, where he after

wards spent the greater part of his life, and never resumed his labours in the university. He was however so fortunate as to have a son, to whom, though very young, he could commit the care of them with the greatest confidence. Mr. Dugald Stewart, having begun to give lectures for his father from the period above men. tioned, was elected joint professor with him in 1775, and gave an early specimen of those abilities, which have not been confined to a single science.

After mathematical studies (on account of the bad state of health into which Dr. Stewart was falling) had ceased to be his business, they continued to be his amusement. The analogy between the circle and hyperbola had been an early object of his admiration. The extensive views which that analogy is continually opening; the alternate appearance and disappearance of resemblance in the midst of so much dissimilitude; make it an object that astonishes the experienced, as well as the young geometrician. To the consideration of this analogy, therefore, the mind of Dr. Stewart very naturally returned, when disengaged from other speculations. His usual success still attended his investigations; and he left among his papers some curious approximations to the areas, both of the circle and hyperbola. For some years, towards the end of his life, his health scarcely allowed him to prosecute study even as an amusement. He died the twenty-third of January, 1785, at sixtyeight years of age. See vol. i. Edinburgh Transactions.

STHENIA, a term employed by the followers of Dr. Brown, to denote that state of the body which disposes to inflammatory diseases, in opposition to those of debility, which arise from asthenia. Dr. Struve in his work on the "Art of prolonging the Life of incurable Persons," gives a few of the theorems after the manner of Brown.

A

He says a stronger stimulus does not, as is commonly believed, destroy a weaker; it only lessens, in a greater or less degree, the force of the latter. Sthenia is always more violent when it is preceded by a considerable asthenia, and vice versa. famished person suddenly filled with food dies apoplectic. Drunkards, if they immediately begin a total abstinence from wine, expose themselves to incurable dis. eases. Sthenia becomes more violent, in proportion as it alternates more complete. ly with asthenia, that is to say, in proportion as the habit is more frequently exposed at one time to sthenic affections, and at another to asthenic. By this perpetu

al irritation, the organization becomes so susceptible that it is very liable to suffer in the highest degree from sthenic diseases. This principle is of the greatest importance for practitioners to be aware of, since it proves that a sudden transition from one extreme to another (as, for example, from cold to heat, taking cold liquors when the body is hot, which often destroys the tone and energy of the stomach,) may lay the foundation of an incurable disease, which sometimes remains long concealed, and then shows itself by the most alarming symptoms.

STICK, the same as baton, an instrument of dignity, which is occasionally carried by persons and officers in high situ ations, particularly by such as are in waiting near the royal person.

STICK, gold. An officer of superior rank in the life-guards so called, who is in immediate attendance upon the King's person. When his Majesty gives either of his regiments of life-guards to an officer, he presents him with the gold-stick. The colonels of the two regiments wait alternately, month and month. The one on duty is the called the gold-stick in waiting, and all orders relating to the lifeguards are transmitted through him. During that month he commands the brigade, receives all reports, and communicates them to the King. This temporary command of the brigade does not, however, interfere with the promotions that may be going forward, as each colonel lays those of his own particular corps before his Majesty. Formerly the gold-stick commanded all guards about his Majes ty's person. On levees and drawingroom days, he goes into the King's closet for the parole.

STICK, silver. The field officer of the life-guards, when on duty, is so called. The silver-stick is in waiting for a week, during which period all reports are made through him to the gold-stick; and orders from the gold-stick pass through him to the brigade. In the absence of the gold-stick, on levees and drawing room days, he goes into the King's closet for the parole.

STIGMA, in botany, the summit of the style, the female organ of generation in plants, which receives the fecundating dust of the tops of the stamina, and transmits the effluvia through the style into the heart of the seed-bud, for the purpose of impregnating the seeds. Most plants have a single stigma, but the lilac has two, the bell flower three, and in others there are four and five. The stigma, when single, generally terminates