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lumns. Thus it attempts to fix and record the position and progress of the different labours by its reports on the state of sciences published annually in its transactions. Thus it directs the attention of the labourers to those gaps which require to be filled up, if the progress is to be a safe and steady one. Thus it comes forward with a helping hand in strive ing to remove those impediments which the unaided efforts of the individual labourer have been or may be unable to overcome.
Let us follow the activity of the association in these three different directions. The reports on the state of science originate in the conviction of the necessity for fixing, at given intervals, with accuracy and completeness the position at which it has arrived; for this object the general committee of the association intrusts to distinguished individuals in the different branches of science the charge of becoming, as it were, the biographers of the period.
Having noticed the great genius and labours of the deceased philosopher, Humboldt (the anniversary of whose birth, by a singular coincidence, happened that day), his Royal Highness thus concluded: Philosophers are not vain theorists, but essentially men of practice; not conceited pedants, wrapped up in their own mysterious importance, but humble inquirers after truth, proud only of what they may have achieved or won for the general use of man. Neither are they daring and presumptuous unbelievers—a character which the ignorant have affixed to them—who would, like the Titans, storm heaven by placing mountain upon mountain, till hurled down from the height attained, by the terrible thunders of outraged Jove; but rather the pilgrims to the Holy Land, who toil on in search of the sacred shrine, in search of truth, God's truth, God's laws, as mani. fested in His works in His creation.
"WHAT TIME IS IT?” AN ACCOUNT OF TIME-KEEPERS, OLD AND NEW.
MR. W. H. BAILEY.
[Tue following interesting lecture on Time-keepers, old and
new, was delivered at Elland, Yorkshire, under the pecu. liar circumstances stated at the close. The Rev. H. Coghlan presided, and introduced the lecturer with some appropri. ate remarks on punctuality. We had the gratification of inspecting the large clock made by Messrs. John Bailey and Co., Albion Works, Salford, for the turret of Elland Parish Church, and must say that it was an admirable specimen of horological mechanism.]
WHAT TIME IS IT? This is a question often asked and answered; and various and ingenious have been the means employed in different ages, to enable that response to be given correctly.
The Sun-dial, the Clepsydra, the Sand-glass, and the Clock with weights and wheels, have in turn been used to indicate the lapse of time. And we may easily arrive at the conclusion that before these artificial means were employed, nature gave abun. dant proof of the time of day by means of the length of the shadow of men, rocks, and trees, caused by the reflection of the sun. In the short space of time I have to deliver a few remarks upon teresting and fruitful subject, I hope to be able to give a summary of the rise and progress of time indicators. All writers seem to agree that the first description of time indicators were sun-dials, and that the first upon record is that of King Ahaz, mentioned in the 20th chapter of the Second Book of Kings, although nothing is known of its form. The Prophet Job says “the servant shall long for the coming of his shadow.” The earliest sun dial of which there is any authentic record, is that of a Chaldean philosopher, by name Berosus, who flourished about 540 years B.C.
Aniximander probably became acquainted with sun-dials through the intercourse he had with the Chaldeans,—he having introduced the first to the Greeks. An ancient sun-dial mounted upon
the shoulders of a Hercules, was discovered at Ravena about 150 years ago. A sun-dial was found at Tusculum, near Rome, in the year 1726, and this dial forms the subject of a dissertation by an Italian antiquarian, who supposes it to have been the one Cicero speaks of, who in a letter mentions his having sent a horologium to his villa near Tusculum. There is a dial in the Elgin Collection of the British Museum, which indicates upon four sides; and is supposed to have been fixed up at one of the cross-ways of Athens, it having been found in that city.
The ancients made sun-dials of many curions forms. Several have been discovered bearing the form of a ham; one of which was found at Herculaneum in the year 1754. It has not been discovered what antiquity they bear, but it will be very evident that this form could not have been used by the Jews, as it represents a limb of that quadruped which every true Israelite holds in abhorrence.
Another dial, similar to this, was discovered at Portico in 1755. A sun-dial taken from the Samanites by Pappirus Cursor, was set up at Rome B.C. 301. Valerius Mesela, the consul, placed in the forum a dial which had been brought from Catana, in Sicily, in the first Punic War, B.C. 261. The Romans were not at that time aware that a dial constructed for one latitude, was not suitable for that of another;—which, of course, rather puzzled them.
one more sure
In one of the comedies of Plautus, an old writer, he causes a Parasite to declaim as follows:
“The gods confound the man who first found out
How to distinguish hours ; confound him, too,
Shrunk up with hunger, creep along the street.” There is a sun-dial at Stubb Hall, Linn of Campsey, near Perth, which, from the inscription upon it, appears to have been erected by John Earl Percy, in the year 1578. It is in the form of an elegant pillar; at the upper part there are four dials for indicating the time, facing the points of the compass, respectively north, east, south, and west; lower down the pillar there are four more dials, looking north-east, northwest, south-east, and south-west ;-thus indicating upon eight separate dials.
It has been said that the regular motion of dropping water applied for indicating time, was in use before the introduction of sun-dials. There is no evidence to prove this assertion; but it is very certain that Clepsydra, or Water Clocks, were used by the inhabitants of China, Judæa, Chaldea, Egypt, and Greece, from a very remote period; and when Julius Cæsar brought his arms into Britain, he found them here, and by their means observed that the nights in this country were shorter than in Italy. The principle of the Clepsydra was as follows in a wood frame were two vessels, one placed above the other; in the bottom of the upper vessel was a small aperture; the lower vessel contained a wood float with a cord attached to it, which cord passed over a pulley with indications upon it. Their mode of action was as follows :—The upper vessel was filled with water, and the water passing through the small aperture into the lower vessel, caused the float to rise, and thereby actuate the pulley with the indications upon it. There were a great many descriptions of Clepsydra, differing in construction only, but not in principle, from the one I have mentioned. It may be interesting to note that at the present day a similar apparatus with float and indicating pulley, is in use for indicating the fluctuation of water in steam boilers. Plato is said to have invented a Clepsydra producing musical sounds, to indicate the hour of the night, when darkness prevented the dial from being seen. Pliny informs us that a Clepsydra was brought from the East by Pompey, and by it the speeches of the Roman orators were limited. And I think it would considerably facilitate business if some such method could be brought to bear upon some of the verbose legislators in the British Senate, -obtaining (as the patentees of improved steam engines have it) "greater speed with less consumption of fuel."
The sand-glass is said to have been first used in Alexandria, about B.C. 140; and no doubt its form is familiar to most of you. In consequence of its cheapness, portability, and simplicity, it has continued in use in this country up to a very recent date. At the present day the sand-glass is in use as an egg-boil. ing indicator : they are also used for philosophical experiments, and for indicating for a ship's log line at sea.
Alfred the Great, a man of keen perception, knew that division of labour was half the labour done. He divided his day into three parts of eight hours each the first he devoted to sleep, to meals, and to exercise; eight hours were absorbed by affairs of government; and eight were given to study and devotion. Alfred indicated his time by the constant