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ost, crushed by a superincumbent weight greater than it could É. In this order, continued subjects began to appear on the frieze, which in the Doric were considered the exception to the rule. The cornice of the entablature was also enriched with exquisite mouldings, and decorated with sculptured ornaments. he edifices constructed after the Ionic order were numerous and magnificent: such as the temples of Bacchus, at Teos; Apollo, at Miletus; Minerva, at Priene and Tegea; and of Diana, at Magnesia and Ephesus. This order was also employed in the construction of the Erectheum, or the temples of Minerva Polias and Pandrosus, in the Acropolis at Athens; of the Delphic Apollo and of -AEsculapius, in the same city; and in that of Juno, in Attica. The temple of Diana, at Ephesus, was justly deemed one of the seven wonders of the world. The architect who traced the plan of this temple was Ctesiphon, who flourished about 540 B.C., and it was partly executed under his direction and that of his son Metagenes; but it was completed by other architects, who worked upon it after these, for the space of more than two centuries. Witruvius says that the form of this temple was dipterick (two-winged), that is, surrounded with two rows of columns in the form of a double portico. It was about 426 feet long, and 216 broad. In this temple there were a hundred and twenty-seven columns of marble each sixty feet high, given by as many kings! Thirty-six of these columns were carved by the most excellent artists of their times. Scopas, one of the most celebrated sculptors of Greece, executed one which was the finest ornament of this magnificent structure. All Asia had contributed with incredible ardour to the erection and decoration of this temple. Vitruvius informs us that Demetrius, whom he calls the servant of Diana, and Paconius, the Ephesian, finished this temple, which was of the Ionic order. History records the remarkable fact that this temple was burned to the ground on the day that Alexander the Great was born; which suggested the waggish conceit to an historian, that Diana was so busy at the labour of Olympia, the mother of the hero, that she could not spare time to preserve her temple. This same Alexander, it is said, offered to rebuild it at his own expense, provided the Ephesians would consent that he should have the sole honour of it, and that no name should be added to his in the inscription to be put upon it. The Ephesians, not approving this condition, concealed their refusal of his offer by saying, “that it was not consistent for one god to erect a monument to another.” This temple was rebuilt with still greater magnificence than at first. The truth of this may be gathered from the words of the sacredhistorian, in reporting the speech of Demetrius the silversmith, who made silver shrines for Diana, to the workmen of like occupation: “Sirs, ye know that by this craft, we have our wealth. Moreover, ye see and hear, that not alone at Ephesus, but almost throughout all Asia, this Paul hath persuaded and turned away mucho saying, ‘that they be no gods which are made with hands:" so that not only this our craft is in danger to be set at *..."; but also that the temple of the great goddess Diana should be despised, and her magnificence should be destroyed, whom all Asia and the worldworshippeth.” Such was the glory that attended the worship of “the thing that fell down from Jupiter,” and such was the terror of the Éphesians that their temple would be destroyed a second time, that, in the words of the sacred historian," when they heard these sayings they were full of wrath, and cried out: Great is Diana of the Ephesians;” and having assaulted Paul, and created a violent uproar, the mob continued to utter the same cry with. out intermission, for “the space of two hours,” in the chief city of Asia.

Fig. 14.

Ionic Order.

The temple of Diana at Magnesia was built under the direction of Hermogenes. He made its general dimensions the same as for a double range of columns; but, in order to afford more space in the porticoes, he omitted the inner range, Thus a clear space was left between the outer range and the body of the building; and thus he established the style called the pseudo-dipterick. Witruvius speaks with great veneration of this architect. The temple of Minerva Ulea at Tegea, designed and erected under the direction of Scopas, was of singular construction. The peristyle of the temple was of the

Ionic order; the interior was divided into three aisles by two rows of Doric columns, and over these were placed others of the Corinthian order. The sculpture upon the two pediments were executed by the artist himself. The simplicity and severity of the Doric order having now Fig. 15.

been abandoned, the artists of Greece Proper, not to be behind the inventors of the Ionic order, by an effort of genius, gave birth to a third order, which surpassed the Ionic in delicacy of proportion and richness of decoration; this order was named the Corinthian. The merit of its invention is ascribed to Calliinachus, a sculptor of Athens, who lived about the period when the Peloponnesian war was brought to a close (b.c., 404). He is said to have taken the idea of o this order from observing the leaves of the acanthus growing, round a basket - which had been placed, with some favourite trinkets, upon the grave of a young Corinthian lady; the stalks which rose among the leaves having been formed into slender volutes by a square tile which covered the basket. In the Corinthian order, the column is more elegant, and the capital longer and more ornamented than in the Ionic, spreading in the form of a basket and commingling the richest and lightest vegetation, with the decorations of preceding orders. The top of the capital, instead of being square, assumes the curvilinear form, having angular projections supported by elegant volutes. The mouldings possess more beautiful ornaments than those of the Ionic or the Doric; the frieze is usually | ornamented with scrolls of foliage; in the cornice, the corona is supported by | modilions, which represent the extremities of the beams of the roof, and are usually carved into a scroll (see fig. 15). These elegant improvements introduced into their orders, rendered the Greeks the real masters of architecture; because, previous to their invention, the Egyptians and the Asiatic nations in general, followed no precise rule in their constructions; but, as soon as the orders were founded on rational proportions, of an exact and invariable nature, they were imitated in the edifices of every other nation. While awarding every credit to the ingenuity of the Greeks, however, it must not be forgotten that in the columns of several temples in Upper Egypt, whose shafts represent bundles of reeds or lotuses bound together in several places by fillets, the capitals are formed by several rows of delicate leaves. In the ruins of Ellora, in India, the capitals of the columns are also composed of similar ornaments; and the Persians, at their great festivals, were accustomed to introduce ornaments of flowers at the tops of the pillars in their public apartments. From tradition, report, or personal observation, Callimachus might be made acquainted with these examples, and might be led to the composition of the Corinthian capital, the chief ornament of the Greek school. The Corinthian order, although distinguished for its richness and even luxuriousness of decoration in all its details, is essentially the most simple in its

Corinthian Order.

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general character, and easiest in execution. The finest examples of this order were to be seen at Athens, in the monument of Lysicrates, the Tower of the Winds, the Stoa or public piazzas, and the Arch of Adrian, at Athens; the Pantheon of Agrippa, and the three columns of the Campo Vaccino, at Rome. The Corinthian order appears to have been but partially employed in Greece before the time of the Roman conquest; but the Romans themselves employed it to a great extent in every part of their empire; hence, it is in edifices constructed under their influence that the most perfect specimens are found. It was only in the construction of temples that the turbulent states of Greece could unite; and in consequence of this union, they constructed edifices of great magnitude and splendour. Many of this description were built and maintained at the expense of confederate states, and even of all Greece: such were the temples at Delphi, Delos, Ephesus, Olympia, Eryx, &c., and these temples had territorial revenues, besides being enriched by private donations. The Greeks appear to have made the greatest progress in the arts, and to have constructed the most admirable of their edifices, during the period from the age of Solon and Pythagoras to the era of Alexander the Great. Their architecture prevailed in the countries where they extended their influence along the coast of Asia. Alexander and his successors introduced it into Egypt, and probably in the cities he built on his route to India. To the westward it extended to Sicily, Italy, and the south of France. After the brilliant period to which we have alluded, the manners of the Greeks became Asiatic; heir sublime spirit of independence was subdued; and ...though they continued for ages to be the instructors of their toman conquerors, their glory in the arts declined, and with : the purity and elegance of the Greek architecture.

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measuring and indicating time, such as clocks and watches, Such machines, in his day, presented a strange contrast to those now in daily use. A great improvement in the construction of clocks was effected, when Clement, a London clockmaker, in 1680, introduced an invention of Dr. Hooke, by which a less maintaining power, than was previously in use, was employed to carry a heavier pendulum, which, making smaller swings or arcs of vibration, met with less resistance from the air, and, therefore, performed its motions with greater regularity. Nor was Hooke less successful in improving the watch. To him is justly attributed the first idea of the balancespring, one of the extremities of which is fastened to a point, independent of the balance, while the other is attached near its axis; thus regulating the beat and producing equable motion; and answering the same purpose in watch-work that the pendulum does in clock-work. This improvement was not gained, however, without difficulty. Hooke's first balancespring was straight, and acted very imperfectly; but he soon perceived its defects, and set himself steadily to obviate them, by adopting first the cylindrical, and afterwards the flat spiral spring. *:::find the longitude at sea—that is, the distance of the meridian of any place eastward or westward from the first or fixed meridian of any country—was meanwhile a problem, to which the attention of mariners and mathematicians had been anxiously directed. Indeed, so long ago as 1598, Philip III. of Spain offered a reward of 1,000 crowns for its solution. Not long afterwards, the States-General of Holland promised 10,000 florins to any one who should achieve the solution of the same problem. The British parliament, in 1714, went beyond these premiums, and empowered commissioners, to introduce a bill for a sum not exceeding £20,000 for defraying the cost of the necessary experiments for ascertaining the longitude; and still further, for granting a proportionate reward to any one who should make a satisfactory advancement towards this grand object. With wealth and fame in prospect, innumerable and unsuccessful attempts were made to gain the rize. P Previous to this period one experiment had been made by Major Holmes, in a voyage from the coast of Guinea in 1665, which answered so well that the celebrated Huygens, who had paid great attention to watches, and had written a treatise on their use in finding the longitude at sea, determined to improve the structure of the watch as an instrument for this purpose; but the variations of heat and cold caused such irregularities of action that, unless these could be remedied, he found that a watch would be of little use in determining the longitude. Far more, indeed, is involved in the production of such a machine than is ordinarily imagined. To become a good watchmaker it is necessary to be an arithmetician, in order to find accurately the revolutions of each wheel; a geometrician, to determine correctly the curve of the teeth; a mechanician, to find precisely the forces that must be applied; and an artist, to be able to put into perfect execution the principles and rules which these sciences prescribe. He must know how fluids resist bodies in motion; and be well acquainted with the effects of heat and cold in different metals; in addition to these acquirements, he must be endowed by nature with a happy genius, to be able to apply them all in the construction of an accurate measurer of time. No one in pursuit of such a rare combination of qualities would probably have gone to a young carpenter, with no ad. vantages of education, and whose knowledge of mathematics appears to have been derived solely from a manuscript, as above mentioned. And yet, before Harrison was twenty-one years of age, he had constructed two clocks made entirely of wood, and without any instruction whatever in the art; while his residence on the coast had directed his mind to the formation of timekeepers, adapted to the purposes of navigation. On this subject he appears to have reflected for many successive years, and to have become perfectly acquainted with the difficulty which Huygens felt, but was unable to surmount. For though every part of a clock were constructed with the greatest perfection, its performance would manifestly, be very inaccurate, unless it were provided with the means of compensating for those changes which result from a variation of temperature, since almost all substances expand by heat and contract by cold. Accordingly a very minute difference in the length of a

pendulum, arising from this natural cause, will produce a serious influence on the rate of the going of a clock. For, if this alteration be so trifling as to cause either an increase or decrease of the time of each vibration of only 1-1440th part of its whole duration, it will occasion the clock to lose or gain a minute in every twenty-four hours—a minute being the 140th part of a day. The problem, therefore, involved in the instance before us is, How shall a timekeeper be constructed so as neither to lose nor gain during a voyage from our temperate climate, to the torrid or the frigid zone? The solution of this problem was practically effected by Harrison, in his invention of the gridiron pendulum. This pendulum takes its name from its form, which consisted of a frame of nine parallel bars; four of steel, and four of brass, while the centre bar of steel is fixed at top to the cross bar connecting the two middle brass bars, slides freely through the two lower bars, and bears the pendulum bobs. The remaining bars are fastened to the cross piece at both ends, and the uppermost cross piece is attached to the axis of suspension. . It is easy, therefore, to see that the expansion of the steel bars tends to lengthen the pendulum, while that of the brass ones tends to #. it; and consequently, if the two expansions exactly counteract one another, the length of the pendulum will remain unchanged. The relative lengths of the brass and steel bars are determined by the expansions of the two metals, which are found by experiments to be, generally, nearly as 100 to 61. With equal ingenuity, and as the result of long-continued and careful thought, Harrison applied the compensatory principle to a watch, by the construction of the compensation balance, o: also, on the unequal expansion of two different metals. In this instance, the circular arms of the balance is a compound bar of brass and steel, the brass being on the outside: this combination was attended with precisely the same successful result. After having given himself, for a long time, exclusively to the construction of timepieces, Harrison came to London in 1728, at the age of thirty-five, bringing with him descriptive drawings of a machine for determining the longitude at sea, in expectation of being engaged to make one for the Board of Longitude. His invention was examined by Graham, the celebrated mathematical instrument maker, who advised Harrison, instead of presenting merely his drawings, first to complete the machine, and then to apply to the Board of Longitude. He therefore went home, and seven years after, returned to London, with the first chronometer; in fact, a large watch, by which he considered the longitude at sea might be correctly determined; its variations during several years, not exceeding a second in a month; thus incomparably surpassing all timemeasurers previously constructed, in this or any other country. In 1736 its accuracy was fully brought to the test in a voyage to and from Lisbon, during which it corrected an error of a degree and a half in the computation of the ship's reckoning. Public encouragement was now given to him, and, by the year 1761, he had completed three chronometers—the last being the most accurate. So satisfied was he with this one, that he

applied to the commissioners of longitude for leave to make

an experiment with it in a voyage to the West Indies, in compliance with the act of parliament. The solicited permission was granted; but, in nonsideration of Harrison's advancing years, his son was allowed to proceed to Jamaica instead of himself. In order that our readers may understand the utility of this machine, we may just glance at its application., When a chronometer is set to the time of Greenwich, which is that of our first meridian—now the invariable practice with all captains sailing to a great distance—and is carried abroad in a vessel sailing from this meridian, a chronometer affords the means of ascertaining the longitude of any place, by simply observing the instant that the sun reaches the meridian of that place,— that is, when it is midday there, or twelve o'clock at noon, and then observing the difference between this time and that shown by the Greenwich chronometer, which must necessarily be different, if the meridian of the place be different from that of Greenwich; for this difference at once gives the mariner his longitude, by allowing 15 degrees east or west for each hour of time, or 15 minutes of a degree for each minute of time; the place being in east longitude, when the time at the place is

later than that at Greenwich; and in west longitude when it is earlier. Thus, suppose the mariner takes the meridian altitude of the sun at sea, and finds that it is noon at the ship, while it is eleven o'clock by the Greenwich chronometer, then the meridian of the place at which he has arrived must be 15 degrees east of Greenwich; while, if the chronometer tells it is one o'clock at Greenwich, the longitude of the place must be 15 degrees west of Greenwich. By the same mode of observation and comparison, the longitude oil.’ places where the ship may be found, is readily de ined; but this mode of determining the longitude requires as the indispensable condition, the accurate-going of the chronometer. When, therefore, after eighteen days sailing in the voyage which was to test Harrison's chronometer, the vessel was suposed by the captain to be 13 degrees 50 minutes west of ortsmouth, and the chronometer gave 15 degrees 19 minutes, or about a degree and a half more, the variation was considered to be fatal to the invention, and the instrument was condemned as useless. But the son of the maker felt that the actual error might be in the chart, and so firmly did he maintain that Portland Island would be seen on the following day, that the captain was induced to continue in the same course, and the island was actually discovered the next day at seven o'clock. The confidence in the chronometer, previously destroyed, was now restored, and it was increased by the complete fulfilment of Harrison's successive predictions of the times when the several islands would be passed during the remainder of the voyage. When the vesses arrived at Portroyal, after a voyage of 81 days, the chronometer was found to be about five seconds too slow, and on his return to Portsmouth, after a voyage of five months, it had kept time within about one minute and five seconds, which gives an error of about 16 miles—a variation greatly within the limits prescribed by the act of parliament. From this experimental voyage it was rendered evident that peril and ruin would be avoided by those who trusted themselves to the guidance of an instrument like that of Harrison's, so wonderfully improved in comparison with all that were constructed before his time. A further test was now allowed the chronometer, in a voyage undertaken by the younger Harrison to Barbadoes; and having now fully complied with the requirements of the act of parliament, the first chronometer-maker applied for, and received the proposed reward of £20,000. Large as the sum appears it was only an appropriate reward for the devotion of extraordinary talents, with unwearied perseverance during a space of forty years. The success which accompanied this invention resulted in the present highly advanced state of horology, the perfection of which as a scientific art is, perhaps, only paralleled by the perfection of astronomy as an artistic science deeply indebted to it. Indeed, to the perfection of both may be ascribed in almost every respect, the present improved condition of society. #ion employed the latter part of his life in constructing a fifth chronometer, which he executed so well that after a ten weeks' trial in the king's private observatory at Richmond, it was found to have erred only four-and-a-half seconds. He died at his house in Red Lion-square, London, March 24th, 1776; leaving behind him an impressive lesson of arduous, and successful perseverance. How accurately chronometers have since been made to go, and with what utility to navigation, will be evident from the statement of the following facts by Dr. Arnott -“After several months spent at sea, in a long passage from South America to Asia, my pocket chronometer and others on board announced one morning that a certain point of land was then bearing north from the ship, at a distance of fifty miles; in an hour afterwards, when a mist had cleared away, the looker-out on the mast #. the joyous call of “Land ahead l’ verifying the reports of the chronometers almost to one mile, after a voyage of thousands of miles. It is allowable at such a moment, with the dangers and uncertainties of ancient navigation before the mind, to exult in contemplating what man has now achieved. Had the rate of the wonderful little instrument, in all that time, been quickened or slackened ever so slightly, its announcement would have been useless, or even worse; but in the night and in the day, in storm and in calm, in heat and in old, its steady beat went on, keeping exact account of the rolling of the earth and of the stars; and, in the midst of the trackless

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Alv to tell its - - Mert, of Latin origin (mors, death, genitive mortis), forms the

immortal; mortgage, is a dead gage or \ledge, –that is to say, something, so pledged, as what are called \o or writings, so that it cannot be used for raising money.

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“Our prayer hath

No powerto pass; and thou hast made us fall,

As refuse and off-scouring to them all." “Whence it follows that these were nations not descending from us, but born with us; not our off-spring, but our brethren.”—South. Qeto, also octa, of Latin origin (octo, eight), appears in octagon, eight-angled; octosyllable, of eight syllables; octoteuch (teuche, Gr, a fold or volume), the first eight books of the Old Testament. 9iy, of Greek origin (oligos, a few), is the first part of oligarchy.(arché, Gr. government), government by a few; oligarch, one of a small number of rulers, Omni, of Latin origin (omnis, all), is seen in omniscient (scio, Lat. I know), all knowing; omnipotent (potens, Lat. powerful), all-powerful ; omnipresent, existing everywhere; omnivorous, alldevouring. Ortho, of Greek origin (orthos, straight, right), as in orthodoxy, right opinion ; orthogonal, right-angled; orihopedic, right-footed, &c. - “Athanasius is commonly accounted the very rule of orthodoxality in this point.”—Cudworth, “Intellectual System.”

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