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burning of candles, which were all made of one regular size and weight: they were notched upon the stem at regular distances. These candles were 12 inches long: six of them, or 72 inches of wax, were consumed in 24 hours or 1440 minutes; and thus supposing the notches at intervals of one inch, one inch would mark the lapse of 20 minutes. It appears that the candles were placed under the special care of his mass priest or chaplain. It was soon disco. vered that the wind rushing through the window and door, and numerous chinks in the wall of his palace, consumed the wax in an irregular manner. Nothing daunted, Alfred soon overcame this difficulty: he discovered that thin sheets of horn were transparent; accordingly, with this material and wood, he constructed a case for his candles, and hence the inventor of horn lanterns is said to be Alfred.

In the Crystal Palace, Sydenham, are some clocks manufactured by a firm called “The London Atmospheric Clock Company.” The clocks are similar to a thermometer; a glass tube with a short column of mercury in it, is placed upon a board with indications upon it; the descent of the mercury in the tube indicates the hour of the day,-quarter hours being the smallest interval indicated by those I saw. When the mercury falls to the bottom of the tube, it is reversed in a similar way to that of a sand-glass. These clocks are made and finished in a very neat style, and display considerable ingenuity. They are sold for about 5s. each; but as time indicators, in my opinion, they are a retrograde movement.

The information respecting the first clocks indicating by means of weights and wheels, is of a scanty nature. Gesner, an old English writer, says that in 1326, Richard of Wallingford, Abbot of St. Albans, "by a miracle of art" constructed a clock which had not its equal in Europe, and was called “Albion" by its inventor. Captain Smith, in a communication to the Antiquarian Society, in 1851, states that there is at present in Dover Castle a clock bearing the date of 1348. Charles the Fifth, surnamed the Wise, of France, caused a clock to be made for his palace, by De Vick, a German. This clock had a crown wheel escapement, similar to that of a bottle-jack at the present day. In 1382, upon the French entering the city of Cortray, the Duke of Burgundy ordered a clock which struck the hours to be taken away: it is at present at Notre Dame. The workmanship of these early clocks was of so rude a character, that minutes were too small for them to indicate; in fact, most of the ancient clocks were made with the hour hand only. There is a clock in the church of Rye, the dial of which is rather less than 8 feet in diameter. It strikes the hours and quarters, and has a pendulum 18 feet long; the bob is of lead, and weiglıs about 56lbs. There is a tradition in the town that this clock was taken from the Spanish Armada, in the year 1588, and presented to the town by Queen Elizabeth. This cannot be founded on fact, as will be seen from the following extract:“1513.—-Paid the cooper for a barrel for the chime 6 2 1515.-For working upon the frame and dial of

the clock in the steeple..
The man who made the clock-work and dial 2 6 8
The man of Winchelsea, who made the

clock-work, in full payment of his
bargain

..0 6 8 1561.-For making the chimes to ring

..0 16 There is every reason to believe that the pendulum is an addition to the clock since the above dates, and that it formerly had a crown wheel escapement, similar to that in De Vick's clock: it is now going. I am indebted to the courtesy of W. Holloway, Esq., of Rye, for the foregoing particulars.

The long pendulum, as used at the present day, is said to have been first applied to a clock, and placed in the tower of St. Paul's Church (since burnt

0 2 0

1 16 0

The house over the clock ..

down), London, in 1641. Galileo applied a long pendulum to a clock in Venice in 1649. Soon after the introduction of the long pendulum, it was found to be affected by the variations of the tempe. rature,- becoming_longer in damp weather, and shorter in dry. To remedy this evil, in the year 1721, Graham invented a pendulum consisting of a steel rod, the bob a glass jar containing mercury; the expansion and contraction of the rod is compensated by the opposite expansion and contraction of the mercury in the bob. This pendulum was found to be very effective. Numerous pendulums have been contrived at various times, since that period, consisting of metallic rods, &c., expanding in opposite directions. About 35 years ago, a very simple and cheap compensating pendulum was invented by Professor Bailey, Secretary of the Astronomical Society, London. The principle of Bailey's pendulum, is that of a rod of well-seasoned pine, varnished; the bob of lead, and cylindrical in shape, with a hole through the centre, into which the rod is inserted. The bob rests upon a nut at the bottom of the rod, and simultaneous expansion of the rod and bob counteract each other. The wheels of a clock may be finished with great precision and great care taken to reduce the friction, and the mechanism may be unexceptionable; but it is all futile if a clock is not furnished with a good compensating pendulum. A great many of the public clocks in this country, have been greatly neglected upon this important point. I have seen highly-finished clocks, with iron pendulum rods 18 feet long, and less; and in consequence of the great expansion and contraction of metal rods of so great a length, their variations from true time is considerable ; for if a clock with an iron pendulum of the length I have mentioned, is regulated to keep time in the summer, it will in the winter lose about five minutes per week.

ment.

The anchor escapement was invented by the celebrated Dr. Hook, and introduced by Clements, a London clockmaker, about the year 1680. This escapement, although very good in some respects, causes a retrograde movement in the wheels of the clock, and in consequence has been called the “recoil escapement.” Graham, to do away with the recoil in this escapement, invented the dead-beat escape

The wheels in this escapement are kept in a state of rest or repose during the oscillations of the pendulum, except at the moment when it receives its impulse from the escape wheel. The pin-wheel dead-beat escapement is used by some of the best makers of turret clocks; for with this escapement, and a good compensating pendulum, a clock will keep time with a very little variation.

It is supposed that clocks with alarms or striking parts, were first used by monks to arouse them to their devotions. During the 17th century there existed a great taste for striking clocks, which caused the production of an endless variety of them. The repeating clocks were first invented by an English clergyman named Barlow, about the year 1766. The following story is in circulation concerning the late Duke of Bridgewater :—The Duke was one day passing through his works between the hours of one and two, and seeing some of his workmen lounging about, he asked them why they were not at their work? He was informed that they had not heard the clock strike one yet, and that they were “having their dinner-hour." 'He determined that they should not have such an excuse again, and caused the clock to be altered to strike thirteen at one o'clock; and if it has not been altered recently, it strikes that number at the present time. Paulinus, Bishop of Nola, in Campagnia, is said to have invented bells about the year 400; they were introduced into France about the year 500, and were used by the Greeks about the year 884. They were introduced into monasteries in the 8th century, and were general in Europe about the year 900. The first peal of bells is said to have been hung at Crowland Abbey, Lincolnshire, in 960. Bells are liable to be worn through in the two places where the clappers strike: to remedy this evil, Mr. W. L. Baker, a few years ago, invented a simple and ingenious plan, the principle of which is to cause the bell to rotate, by simply turning a worm actuating a worm-wheel fixed upon the crown of the bell. By this means one man is enabled to turn a bell in a few minutes, and present a fresh place for the hammer or clapper to strike upon. A modification of this plan has been adopted by Mr. Denison, for the Westminster Bell. I refer those curious upon bells, to a very able work by the Rev. W. Lukis, M.A., F.S.A., &c., published by J. H. Parker, London, and the authors there cited.

Cast-steel bells were invented by E. Riepe. There were some at the Paris Industrial Exhibition, 1855. The Legion of Honour was awarded, in addition to a gold medal, to their inventor. They are produced at a considerably less cost than bronze or brass bells, and the sound produced by them I consider is equal to that of those composed of the more costly metal. In many of the continental towns are clocks which indicate the various changes in the astronomical world, and actuating curious automaton figures. The most ingenious and intricate of all these, is acknowledged by all parties to be the famous clock at Strasburg Cathedral. This clock is composed of three parts,

respectively dedicated to the measure of time, to the calendar, and to astronomical move. ments. Upon the external dial are indicated the hours, and their subdivisions, as well as the days in the week; it strikes the hours and quarters, and puts in motion divers allegorical figures such as the following :- A figure placed upon a balustrade, turns each hour a sand-glass placed in its hand. A

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