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optical apparatus (including the optic nerve) not become less available, and not unfrequently, at the dependent on disease-viz., short-sight, long-sight, age of 50 or 60, if not much earlier, the power of double vision, colour-blindness, and night-blindness. vision is irrevocably lost, whether through scpara
Short-sight, near-sight, or myopia (derived from the tion of the retina from the choroid, from effusion of Greek words myo, I close, ops, the eye), is often blood, or from atrophy and degeneration of the popularly confounded with dim or weak sight; but yellow spot.' in reality, short-sight applies exclusively to the range In the treatment of myopia the principal objects and not to the power of sight, and a short-sighted are: 1. To prevent its further development and the person may possess the acutest power of vision for occurrence of secondary disturbances; and 2. By near objects. In this affection, the rays which means of suitable glasses, to render the use of tho ought to come to a focus upon the retina converge myopic eye easier and safer. to a point more or less in front of it. The cause 1. To effect, if possible, the first object, the of this defect probably differs in different persons. patient must look much at a distance, but as we It may arise from over-convexity of the cornea or cannot absolutely forbid his looking at near objects the lens, from undue density or abundance of the spectacles must be provided which render vision humours of the eye, from elongation of the globe in distinct at from 16 to 18 inches. Moreover, it is its antero-posterior diameter, or from an imper. desirable that at intervals of a half hour work should fect power of the eye to adjust itself to objects be discontinued for a couple of minutes, and no at various distances. The distance at which working in a stooping position should be permitted. objects are perceived most distinctly by the per- The patient should read with the book in the hand, fectly normal eye ranges from 16 to 20 inches; and in writing should use a high and sloping desk. an eye which cannot perceive objects distinctly 2. The optical remedy for short-sight obviously beyond 10 inches may fairly be regarded as consists in concave glasses of a focus suited to the short-sighted; and in extreme cases, the point of individual case. At first sight, it might be supdistinct vision may be three, two, or even only posed that glasses with a concavity exactly suffi. one inch from the eye. Short-sight is frequently cient to neutralise the defect in the eye, would always hereditary in families. As a general rule, the suffice; and when the glasses are used exclusively inhabitants of towns are much more liable to it than for distant vision (for example, in the double eyepersons living in the country, and students and glass, which is only at intervals held before the eye), literary men are the most liable of all. While in or when the affection is slight, and the eye is otherthe Foot-guards, consisting of nearly 10,000 men, wise healthy, perfect neutralisation is admissible;
not half-a-dozen men have been discharged, nor but so many circumstances forbid the complete have a dozen recruits been rejected on account of neutralisation of the myopia, that an oculist of repu. this imperfection, in a space of 20 years, in one tation should always, if possible, be consulted as to college at Oxford no less than 32 short-sighted men the choice of spectacles. Glasses, if injudiciously (or myopes, as they are termed by some oculists) selected, usually aggravate the evil they are intended were met with out of 127' (Donders, On the Accom- to remedy; and in connection with this subject, we modation and Refraction of the Eye, London, 1864, p. must warn our readers against the prevalent habit 342). The frequency of this affection in the culti- of employing a single eye-glass; it is most prejudicial vated ranks points directly to its principal cause to the eye which is left unemployed, and often leads tension of the eyes for near objects. The myopia to its permanent injury. depending, as Donders believes, upon prolongation Long-sight and presbyopia (derived from the Greek of the visual axis, this eminent physiologist inquires : words presbys, an aged person, and ops, the eye), are
How is this prolongation to be explained ? Three usually considered by English writers as synonymous factors may here come under observation : 1. Pres. terms. Donders, who is now universally accepted sure of the muscles on the eyeball in strong con. as the highest authority on this department of eyevergence of the visual axes; 2. Increased pressure affections, maintains that the term presbyopia is to of the fluids resulting from accumulation of blood be restricted to the condition in which, as the result in the eyes in the stooping position ; 3. Congestive of the increase of years, the range of accommodation processes in the base of the eye, which, leading to is diminished, and the vision of near objects is intersoftening, give rise to extension of the membranes. fered with. As from youth up to extreme old age, That in increased pressure, the extension occurs the vision of near objects becomes progressively more principally at the posterior pole, is explained by the and more difficult, it is impossible to fix any limit want of support from the muscles of the eye at that as the commencement of presbyopia. In practice, part. Now, in connection with the causes mentioned, however, a word is required which indicates the the injurious effect of fine work is, by imperfect condition in which the eye, at an advanced period illumination, still more increased ; for thus it is of life, and sometimes soover, requires convex spec. rendered necessary that the work be brought closer tacles for distinct near vision, as, for example, for to the eyes, and that the stooping position of the reading, and this word is presbyopia. In this head, particularly in reading and writing, is also state, the nearest point of distinct binocular vision increased. Hence it is that in schools where, by is found to lie about 8 inches (or double the ordi. bad light, the pupils read bad print in the evening, nary distance) from the eye, and at this point or write with pale ink, the foundation of myopia Donders arbitrarily places the commencement of is mainly laid. On the contrary, in watchmakers, presbyopia. This condition, which is as natural a although they sit the whole day with a magni- concomitant of advanced life as gray hairs or fying-glass in one eye, we observe no development wrinkles, is occasionally met with in young persons. of myopia, undoubtedly because they fix their In these cases, it generally arises from intestinal irri. work only with one eye, and therefore converge but tation, and may be a precursor of amaurosis ; hence little, and because they usually avoid a very stooping such cases should be carefully watched. In ordinary position.'--Op. cit., pp. 343, 344.
presbyopia, the defect is at once remedied by the So far from short-sightedness improving in use of glasses of low convex power, as of thirty or advanced life, as is popularly believed, it is too twenty-four inches focus, which should, however, frequently a progressive affection; and every pro- only be worn during reading and writing, and not gressive myopia is threatening with respect to the constantly. Although the improper use of convex future. •If," says Donders, it continues progres- glasses is not by any means so dangerous as the Rive, the eye will soon, with troublesome symptoms, l inconsiderate use of concave glasses, the advice of a
gnod oculist regarding the choice of spectacles is lets. The stems of S. are abundant in the coalwell worth his fee.
beds. They are marked by parallel longitudinal Double vision, or diplopia, is of two kinds. It may flutings, and regular scars formed by the base of the arise from a want of harmony in the movenients leaf-stalks, which had fallen off. They are known of the two eyes, the vision of each eye singly being to have attained a height of 70 feet, and a diameter perfect; or there may be double vision with one of 5 feet. The stem rose without branching till eye only. The first form may occur (1) in cases of near the summit, where it branched several times squinting, or (2) in cases of paralysis of one or more dichotomously. The proportion of woody matter of the muscles of the orbit. In cases of Squirting to cellular tissue in the stem was very small. The (9.v.), the vision of the most distorted eye is almost always imperfect; and it is well known that impressions on the two retinæ are similar in kind but dissimilar in form. The mind takes cognizance only of the former; so that a person with a bad squint sees objects with the sound eye only. But if the sight of both eyes is nearly equal, as often is the case when the squint is not very well marked, double vision results whenever both eyes are employed together, in consequence of images of nearly equal intensity falling on non-corresponding parts of the two retinæ. This variety of double vision, although annoying, is perfectly harmless. When double vision arises from muscular paralysis, disease of the brain of a serious nature is to be apprehended, although the affection sometimes appears to arise from exposure to cold. The second form of double vision-viz., double vision with a single eye, is a much more rare affection than the preceding one, and depends upon some irregular
Trunk of Sigillaria rising from the Stigmaria Roots refraction of the cornea or lens.
(E. W. Binney). Colour-blindness is noticed under its own name.
Night-Ulindness, or hemeralopia (from the Greek, woody fibre is characterised by the abundance of signifying • day-sight'), is a peculiar form of inter: scalariform vessels, similar to those which occur in mittent blindness, the subjects of which see per- | Lepidodendron, and in the recent vascular Cryptofectly with an ordinary light, but become entirely gamia. The stem is seldom found preserved so as and almost instantaneously blind as soon as twilight to exhibit any structure, or even its cylindrical commences. It is seldom met with in this country
form ; it generally occurs as a double layer of coal, except among sailors just returned from tropical
shewing on the outer surfaces the scars produced regions. It is frequent among the natives of some by the bases of the leaf-stalks. The form and parts of India, who attribute it, as our own sailors arrangement of these scars have been used to distin. do, to sleeping exposed to the moonbeams. The guish the species, and, indeed, no other materials most probable cause of the affection is, however,
exist, for hitherto no foliage of any kind has been exhaustion of the power of the retina from over
certainly found connected with the trunks. The excitement from excessive light, so that this organ
restoration of the genus has been consequently is rendered incapable of appreciating the weaker quite imaginary. Some, with Brongniart, have stimulating action of twilight or moonlight. All supposed that the trunk terminated in a crown of that suggests itself in the way of treatment is to simple leaves, like that of many palms, and that it protect the eves from strong light dnring the day, I was a gymnosperm near to the Cycads. Others, and to prescribe quinine and a nourishing mixed diet. with King, consider that the fronds of Pecopteris Snow-blindness must be regarded as an allied n.
orded an allied nervosa, which are very abundant in the coal meaaffection to the preceding.
sures, are its foliage, and they would restore it so as
to have the appearance of a modern tree-fern. And SIGHT OF A GUN. See GUNNERY.
others, with Binney, consider that its affinities are SIGILLA'RIA, a genus of fossil plants which are nearer to Lepidodendron, and that some of the of importance because of their singular structure,
numerous fragments which have been referred to and their remarkable abundance in the coal mea
this genus may really be the branches of Sigillaria. sures. They seem to have contributed more than
They would restore it as if it were a huge Lycoany other genus of plants to the formation of coal.
podium, and refer to it some of those fruits which, · The roots of S. are found preserved in the shale under the names of Lepidostrobus and Flemingites. which forms the floor of all coal-seams. These roots
have been described by Brown, Hooker, and Carwere originally supposed to be distinct plants, and ruthers. have received the generic name of Stigmaria. The SIGISMUND, emperor of Germany (1411 most feasible notion, and that generally accepted 1437), was the son of the Emperor Kars IV. He regarding them, was that they were fleshy water. was well educated, and having married Maria of plants, with numerous linear leaves, articulated to Anjou, on her accession to the throne of Hungary the stem by papillæ, which were buried in deep he became chief administrator of that kingdom. cylindrical hollows in the stem. Brongniart first The death of his wife in 1392 made him king of suspected that they were roots, and Binney placed Hungary; and at the head of a numerous army of the question beyond doubt by discovering a speci. (more than 100,000 men, composed of Hungarians, men in which the trunk of a S. rose from the crown French, Germans, and Poles, he attempted to relieve of a Stigmaria. Several observers have subse. the Byzantine empire from the fierce Turks, but quently seen these fossils also in actual contact. It was terribly defeated at Nicopolis (28th September. is believed that the mud (now converted into shale) (1396). On his return to Hungary, he found in which they grew was very soft, and easily per on the throne a new monarch, Ladislas of Naples, mitted the passage of the large roots, while they who imprisoned him (1401); but through the good gave off all round innumerable large hollow root- offices of his elder brother, Wenceslas, he was freed,
and obtained the throne (1402), rewarding his quent invasions of Moscovites and Tartars were elder brother by snatching from him his kingdom repelled as before, and a rebellion of the Wallachs of Bohemia, which he retained for some time. In was puvished by numerous defeats, chief of which 1411, he was proclaimed emperor, on the death of was that of Obertyn (1531). The insolence of the Rupeit. He was present at the Council of Con- Teutonic Order, who had invaded Polish Prussia, stance, which he had prevailed upon Pope John was effectually chastised by S., who defeated their XXIII. to hold for the purpose of putting an Grand Master Albert, bis own nephew, in two great end to the Hussite and other schisms. He con- battles, in the latter of which the knights were tented himself with protesting against the viola- assisted by the Danes (1520). In 1525, he agreed tion of the imperial safe-conduct which was given to confer on Albert the title of Duke of Prussia to Huss, and ultimately consented to his judicial | (now known as East Prussia), on condition of fealty murder, for the purpose, as his apologists say, of and homage. The dukes of Prussia continued as conciliating the council, and so settling the dis- vassals of the Polish crown till 1657. In 1526, S. putes concerning the papacy His succession to alone of the monarchs of Christendom lent aid to the throne of Bohemia, after his brother's death, Hungary against the formidable array of Solyman was opposed by the Hussites, who were now in the Magnificent, and a numerous force of Polish insurrection; and after a fruitless attempt to con- cavaliers fought bravely on the fatal field of quer them, he confined himself to the defence of Mohacz (1526). The only other important event Hungary against the Turks, whom he defeated in a of S.'s reign was the introduction and extension of great battle near Nissa (1419). For ten years after- | Lutheranism in Poland, a change which S. did warıls, he left Germany very much to the guidance nothing to prevent, only taking precautions, and of its self-willed petty rulers, who speedily brought sometimes severe ones, against its affecting the the country into such a deplorable state that they civil and political condition of the country. It were glad to beseech S. to return to the helm of is told of him that, when John Eck exhorted affairs—which he did, but with little good effect. him to take severe measures with the Lutherans, He obtained, by concessions to the Calixtines (q. v.), whom he compared to goats among the sheep the crown of Bohemia in 1436 ; but when he found the faithful Catholics'), S. replied that he was himself firmly seated on the throne, he gradually desirous of being • king of goats as well as king withdrew these concessions, which provoked such of sheep.' After a long and glorious reign, S. died discontent, that his death, 9th December 1437, alone at Cracow, 1st April 1548, leaving the character of averted a civil war. S. left one daughter, Eliza- a just, wise, and magnanimous prince, who had beth, who, by her marriage with Albert V. of restored to his country its ancient prosperity, and Austria, brought Hungary and Bohemia to the had raised it from the very feet of its enemies to a House of Hapsburg. š. possessed a large intelli. worthy superiority over them. gence, and remarkable political talents, but these SIGNALS are the means of transmitting intelli. were much neutralised by his impetuosity, inde. gence to a greater or less distance by the agency of cision, selfishness, and extraordinary avarice; and sight or hearing. Incomparably the most powerful his well-meaning endeavours after peace and medium yet known for this purpose is the electric improvement ended in nothing.
current. See TELEGRAPH. Sound signals have SIGISMUND, worthily surnamed the GREAT, obviously but a short circuit. The electric current king of Poland, was the youngest son of Casimir requires fixed apparatus establishing an actual IV., and was born at Koziénicé, 1467. He was communication between the two points; and is chosen Grand Duke of Lithuania, 1506, and suc- therefore inapplicable to the ordinary cases of ships ceeded to the kingdom of Poland on 8th Decem- | interchanging signals with each other or with the ber of the same year. The affairs of Poland and shore; and, except under unusual circumstances, it Lithuania were at that time in a sad condition; the would not apply to armies maneuvring in the field. southern portions of the country reduced almost to For these purposes, so far as present knowledge a desert by the ravages of the Tartars, while the extends, signals by sight or sound must always be east was continually in dread of the Russians, who practically the resort. had become an independent, united, and power. The ancients seem to have elaborated a fair ful monarchy. The Russians invaded Lithuania, system of night-signals by torches for military pur. and conquered some provinces, but S. gained a poses; but in naval affairs the ships sailed so close brilliant victory over them at Orsza on the Dnieper together, that orders could be communicated by (14th July 1508). Bogdan, Prince of Moldavia and word of mouth, while the turning of a shield from Wallachia, now invaded the southern provinces, as right to left sufficed as sailing directions to the that semi-barbarous race were accustomed to do several lines. In modern times, signalling between without let or hindrance; but he was so decisively ships has become indispensable; but there is prob. routed on the banks of the Dniester, that he gladly ably no department of practical science in which agreed to acknowledge himself a vassal of Poland. progress has been slower, and every so-called Disregarding the suggestions of the pope to head a system of signals has been distinctly without crusade against the Turks, S. next read the Tartars, any system whatever. In the time of James through his general, Ostrogski, a very forcible lesson, II., a signal could only be expressed by flags, in in 1512, against aggressive practices, which cost confusing number, bung in different parts of the them 27,000 men, and assured the tranquillity of vessel. By the commencement of the present cen. his frontier for a long period. His alliance in 1513 tury, thanks to Sir Home Popham and other inwith Stephen Zapoli, voyvode of Transylvania, ventors, the system had been adopted of hanging a whose daughter, Barbara, he also married, alarmed number of flags under one another, each symbol or the Emperor Maximilian, who incited the Russians combination having an arbitrary conventional mean. to resume their aggressions, which that ill-advised ing attached to it. Alterations in the specific flags nation cheerfully agreed to do; paying dearly for have been made from time to time, but essentially their rashness,, for their army of 80,000, which had this is the system now in use. The flags are either invaded Lithuania, was met and cut to pieces (8th square, triangular of the same length, or pendants September, 1814) by Ostroyski, with 32,000 men, at which are pointed and longer. These are of black, Orsza, leaving its standards, cannons, and other white, red, blue, and yellow (in the Austrian ser: arins, 2 generals, 37 princes, 6000 prisoners, and vice alone green is added) in mass or in combination. 30,000 dead in the possession of the enemy. Subse- | Specimens of the flags in use in the present naval SIGNALS.
mode are shewn in fig. 1. The signalmen find, to Colonel Grant, Captain Bolton, Mr Redl, and Lowever, that at a distance blue, red, and black are Lieutenant Colomb, R.N. Their principal object 1 ot readily distinguishable, nor yellow from white. has been so to simplify the telegraph system that
siguals may be niade with any apparatus, or without
in fig. 2. The arms
are heavy, and involve Fig. 2.--Semaphore System.
mechanism ; besides It has consequently been the recent tendency, and which they are not always clear on a ship in apparently most justly, to reduce all the signs to motion beyond a short distance. Very superior black and white, singly or in combination, trusting in visibility and simplicity is Redl's System of to shape for different signals.
Cones. This consists of 4 cones fixed to a mast. There are, however, disadvantages attending flags. The cones are collapsable, and are formed in a In a still day, they are difficult to read; or the wind similar manner to umbrellas. Their usual condi. may so blow that they are only seen end on. At tion is shut, and they can only be held open while sea, the motion of a ship will generally neutralise a rope attached to each is pulled. With cones these drawbacks; but the case is otherwise on of 3 feet base, signalling is rapid and clear up to shore, and it may consequently occur that the ship 5 miles, and the mast can be inserted at any place. can communicate to the land, but cannot get a The system is very simple : each cone represents reply. To obviate this, signals representing solid a number, 1, 2, 3, or 4; then 1 and 4 shewn figures are sometimes employed. To fulfil their represent 5; 2 and 4, 6; and so on, as in fig. 3. conditions, they must appear the same in wḥatever This very elegant system can be applied in military lateral direction seen. But this limits the shapes to cylinders, cones, and the sphere, or combinations of those figures; and as the total number of distin. guishable signs is reduced, signalling becomes reduced from the word-signal to the telegraph. This distinction should be clearly understood, as much is involved in it. A word-signal, as in the present system, is where the whole word or message is sent up at once, and flies simultaneously; a telegraph signal is one in which the letters composing the 11 21 31 41 51 61 21&lo word or numbers representing the signal are shewn separately, and each is removed before another is
Fig. 3.—Cone System. shewn. At sea, the word-system is best, for it involves no act of memory; and memory, even from or naval operations. But its chief beauty is, that a signal to signal, is found difficult by signalmen in person understanding it can make the same signals the turmoil of perhaps storm or fighting. On the without the cones ; for example: if a black flag other hand, the telegraph system involves far simpler represent an open cone, and a white flag a shut cone, apparatus, and the changes can be effected more a ship with 4 black and 3 white flags can make rapidly. As regards the actual time required for a every signal. Again, the arm raised horizontally message, the word-system has the advantage in a may represent the open cone; against the body, the message short enough for the whole to be shewn at shut cone; then two men standing on a cliff are as one time; but otherwise the difference is not good as any signal-post, see tig 4. Or if one person material. If all advantages be balanced, it is probable that the telegraph system will eventually supersede the other entirely. Whether the word or the telegraph system be practised, another question is, whether to spell each word, or to use numerals and a code. Under the latter principle, about 14,000 of the words aud sentences most commonly sent are arranged for easy reference in the signal-book. With the addition of 1 or 2 repeating symbols, the 9 numerals and 0 give combinations 4 together to this number. A combination of figures is arbitrarily assigned to each expression; and the expression is communicated by representing those figures in their
Fig. 4. proper order. With the book of reference at hand, and intelligent signalmen, there can be no doubt of only be present, he may represent an open cone by the superior rapidity of the code.' A code has raising his arm with a handkerchief extended, and a also this further advantage, that the signals repre- shut cone by his arm without the handkerchief. He senting things and not words, it can be made inter has only then to raise his arm four times in quick national, the same symbols representing the same succession, with or without the handkerchief, to make idea in every language. It is then only necessary for the required signal. We have thus arrived at a universal signalling that each nation should concur universal system of the utmost simplicity, which in in the meaning to be attached to the several signs. war, and especially during invasion, might be of Many gentlemen of ability have devoted their atten. inestimable benefit to the nation. The code of sig. tion of late years to the simplification of signals ; nals cannot be too generally diffused by the govern. among whom conspicuous positions must be assigned ment, in order that every man among the publia
may become an amateur signalman on emergency. be adopted we should signal as in fig. 5. It will be A secret code, in which the same numbers have seen at once that this system produces results similar different significations, could always be maintained to Morse's Electric Telegraph. If the distance be for state purposes. It only remains to apply the same system to
8 night-signals. The old naval principle has been to hang dingy lanterns in various shapes-triangles, squares, crosses, &c. Besides requiring large
Fig. 5. bases to be at all visible, this has been found | from the motion of a ship to be nearly useless.
within a mile or so, and the weather still, a bugle Redl's system has been applied by hanging four will answer equally well, long and short notes repre. lanterns in a vertical line to represent the cones, senting the positive and negative cones. and obscuring those which corresponded to shut The fundamental principle of the foregoing system cones. An improvement was found in introducing
| of universal telegraphy, applicable by night or by a red or green light in the middle, to shew the rela- day, by sight or by sound, is to employ two signals tive position of the four. The best night-signals only-one positive and one negative--and to regu. are, however, flashing lights, as introduced by Cap. | late their exhibition by periods of time. tain Bolton, and more elaborately by Lieutenant SI'GNATURE, in Music. In writing music in Colomb, and adopted in the navy. This consists of any key with sharps or flats, the sharps and flats a bright light, covered by a shade, which shade, by belonging to the key, instead of being prefixed to mechanism, can be lifted for any given time, exposing each note as required, are placed together immethe light meanwhile. A flash of about half a second's diately after the clef on the degrees of the staff to duration is negative: a line of 15 seconds, positive. which they belong; and this collection of sharps or Four exhibitions of the light then represent a sym- flats is called the signature. The signatures of the hol as in Redl's cones. If the same nomenclature several keys generally in use are as follows:
MINOR. D G F Bb Eb The minor keys take the same signature with the major keys a third above them.
© Thus, indicates that there are two crotchets, When a new key is introduced in the middle of a piece of music, the signature of the former key must be contradicted, and that of the new one appended. and three quavers, in the measure. When Thus a transition from the key of D major to that
there are four crotchets (or a semibreve) in the of D minor, is indicated thus :
measure, it is usual to write E instead of
SIGNATURE, in Printing, denotes the letters
which are placed at the bottom of the first page of from B major to B minor:
each sheet of a book, to facilitate the arrangement
of the several sheets in the volume. The letters the sharps which are to continue being, in this last employed are those of the alphabet, with the excep. case, for distinctness' sake, appended in addition to
tion of J, V, and W, three letters which have been the contradiction of those that are to be discarded.
invented since the use of signatures was introduced. A transition to another key, which is not to continue
See ALPHABET. As the first sheet of a work, confor any length of time is seldom indicated by a taining the title-page, dedication, preface, &c., is change of signature : but the sharp, flat, or natural generally printed last, the letter A is reserved sign is appended to any note as required, that sign (along with small letters, a, b, &c., should there be affecting all the following notes of the same letter I more sheets of introductory matter) for this, and the in the measure in which it occurs, unless contra | signatures commence with B; after reaching Z, they di sted. A sharp, flat, or natural thus introduced commence again at the beginning of the alphabet, is called an accidental. Two accidentals are the letter being doubled for the sake of distinction
ed in the ascending scale of every minor key. | as AA, or Aa, or more frequently 2A. Should tł to sharpen the sixth and seventh of the tonic
alphabet again be exhausted, 3A, 3B, &c., are ne: Besides the signature of the key, a signature of employed, and so on. This is the method employe time precedes every musical composition. It con. | in Britain ; in France and Italy, figures are generall sists of two figures placed over one another as a used. Signatures (as B2, B3, &c.) are also placeu fraction, the denominator 2, 4, 8, or 16 standing for on certain pages of the same sheet, as a further minims, crutchets, quavers, or semiquavers (i. e., direction to the bookbinder. halves, fourths, &c. of a semibreve), while the SIGNET, in England, one of the seals for the numerator points out how many of these fractional authentication of royal grants. Prior to 1848, all parts of a semibreve are contained in each measure. letters-patent and other documents which had to