- A Tubeless, or 'Aerial' Telescope
From an illustration in the Opera Varia of Christian Huyghens. Attempts were made to evade this unwieldiness by constructing them with skeleton tubes. or , indeed, even without tubes at all; the object-glass in the tubeless or "aerial" telescope being fixed at the top of a high post, and the eye-piece, that small lens or combination of lenses, which the eye looks directly into, being kept in line with it by means of a string and manœuvred about near the ground. The idea of a telescope without a tube may appear a contradiction in terms; but it is not really so, for the tube adds nothing to the magnifying power of the instrument, and is, in fact, no more than a mere device for keeping the object-glass and eye-piece in a straight line, and for preventing the observer from being hindered by stray lights in his neighbourhood. It goes without saying, of course, that the image of a celestial object will be more clear and defined when examined in the darkness of a tube. - Burgmote Horns
Beautiful horns of hammered and embossed bronze belonging to the Corporations of Canterbury and Dover. The right-hand one is from Dover, where it was formerly used for the calling together of the Corporation at the order of the mayor. The minutes of the town proceedings were constantly headed "At a common Horn blowing" (comyne Horne Blowying). This practice continued until the year 1670, and is not yet entirely done away with, as it is still blown on the occasion of certain Municipal ceremonies. The motto on this horn is:— JOHANNES DE · ALLEMAINE · ME · FECIT · preceded by the talismanic letters A·G·L·A, which stand for the Hebrew אַתָּה גִּבּוֹר לְעוֹלָם אֲדֹנָי and mean, "Thou art mighty for ever, O Lord!" The horn, which is 31¾ inches long, with a circumference at the larger end of 15½ inches, is of brass, and is deeply chased with a spiral scrollwork of foliage chiefly on a hatched ground. The inscription is on a band that starts four inches from the mouth and continues spirally. The maker's name is now nearly effaced, but the inscription shows that he was a German, and the date is assigned to the thirteenth century. - Cornemuse, Calabrian Bagpipe, Musette
The Calabrian Bagpipe or Zampogna is a rudely carved instrument of the eighteenth century. It has four drones attached to one stock, hanging downwards from the end of the bag: two of them are furnished with finger-holes. The reeds are double like those of the oboe and bassoon. The bag is large; it is inflated by the mouth and pressed by the left arm against the chest of the performer. The Zampogna is chiefly used as an accompaniment to a small reed melody pipe called by the same name, and played by another performer. The quality of the tone produced is not unpleasing. It has five holes only, and consequently the seventh of the scale is absent, but this can be easily got by octaving the open note of the pipe and covering part of the lower opening of the chanter with the little finger. The Musette, Zampogna, and Cornemuse here shown are from specimens belonging to Messrs. J. & R. Glen, Edinburgh. - Great Telescope of Hevelius
This instrument, 150 feet in length, with a skeleton tube, was constructed by the celebrated seventeenth century astronomer, Hevelius of Danzig. From an illustration in the Machina Celestis. The attempts to construct large telescopes of the Galilean type met in course of time with a great difficulty. The magnified image of the object observed was not quite pure; its edges, indeed, were fringed with rainbow-like colours. This defect was found to be aggravated with increase in the size of object-glasses. A method was, however, discovered of diminishing this colouration, or chromatic aberration as it is called from the Greek word χρῶμα (chroma), which means colour, viz. by making telescopes of great length and only a few inches in width. But the remedy was, in a way, worse than the disease; for telescopes thus became of such huge proportions as to be too unwieldy for use. Attempts were made to evade this unwieldiness by constructing them with skeleton tubes. - Jane Porter
This engraving represents our accomplished author as a lady of a chapter belonging to a chivalric order. The high compliment from a German court was paid to the merit of Thaddeus of Warsaw. This portrait, as contrasted with that of her sister, well justifies the appellation bestowed upon them by mutual friends - they went by the names of L'Allegro and Il Penseroso. - Lamont Harp
The extreme length of the Lamont Harp is 38 inches, and the extreme width 18½ inches. The sound chest, as with other ancient harps, is hollowed out of one piece of wood, but the back has been in this instrument renewed, although probably a long time ago. The sound chest is 30 inches long, 4 inches in breadth at the top, and 17 at the bottom. The comb projects 15½ inches. The broken parts of the bow are held together by iron clamps. - Map of the Moon
In this picture the South will be found at the top of the picture; such being the view given by the ordinary astronomical telescope, in which all objects are seen inverted. - Orbit and Phases of an Inferior Planet
Corresponding views of the same situations of an Inferior Planet as seen from the Earth, showing consequent phases and alterations in apparent size. - Queen Mary's Harp
This venerable instrument, the least impaired Gaelic Harp existing, is known as Queen Mary's Harp. It is small, being only 31 inches high and 18 inches from back to front. It was played resting upon the left knee and against the left shoulder of the performer, whose left hand touched the upper strings. The comb is from 2½ to 3¼ inches high. It is inserted obliquely in the sound chest, and projects about 14 inches. - Showing how the Tail of a Comet is directed away from the Sun
hese mysterious visitors to our skies come up into view out of the immensities beyond, move towards the sun at a rapidly increasing speed, and, having gone around it, dash away again into the depths of space. As a comet approaches the sun, its body appears to grow smaller and smaller, while, at the same time, it gradually throws out behind it an appendage like a tail. As the comet moves round the central orb this tail is always directed away from the sun; and when it departs again into space the tail goes in advance. As the comet's distance from the sun increases, the tail gradually shrinks away and the head once more grows in size (see Fig. 18). In consequence of these changes, and of the fact that we lose sight of comets comparatively quickly, one[Pg 249] is much inclined to wonder what further changes may take place after the bodies have passed beyond our ken. - The 'Ring with Wings.' - Assyrian Form
The 'Ring with Wings.' - Assyrian Form It should, however, be here mentioned that Mr. E.W. Maunder has pointed out the probability that we have a very ancient symbolic representation of the corona [of an eclipse] in the "winged circle," "winged disc," or "ring with wings," as it is variously called, which appears so often upon Assyrian and Egyptian monuments, as the symbol of the Deity. - The comet of 1066, as represented in the Bayeux Tapestry
We have mentioned Halley's Comet of 1682, and how it revisits the neighbourhood of the earth at intervals of seventy-six years. The comet of 1066 has for many years been supposed to be Halley's Comet on one of its visits. The identity of these two, however, was only quite recently placed beyond all doubt by the investigations of Messrs Cowell and Crommelin. This comet appeared also in 1456, when John Huniades was defending Belgrade against the Turks led by Mahomet II., the conqueror of Constantinople, and is said to have paralysed both armies with fear. - The Copernican theory of the Solar System
The Sun, the most important of the celestial bodies so far as we are concerned, occupies the central position; not, however, in the whole universe, but only in that limited portion which is known as the Solar System. Around it, in the following order outwards, circle the planets Mercury, Venus, the Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. At an immense distance beyond the solar system, and scattered irregularly through the depth of space, lie the stars. The two first-mentioned members of the solar system, Mercury and Venus, are known as the Inferior Planets; and in their courses about the sun, they always keep well inside the path along which our earth moves. The remaining members (exclusive of the earth) are called Superior Planets, and their paths lie all outside that of the earth. - The Great Yerkes Telescope
Great telescope at the Yerkes Observatory of the University of Chicago, Williams Bay, Wisconsin, U.S.A. It was erected in 1896–7, and is the largest refracting telescope in the world. Diameter of object-glass, 40 inches; length of telescope, about 60 feet. The object-glass was made by the firm of Alvan Clark and Sons, of Cambridge, Massachusetts; the other portions of the instrument by the Warner and Swasey Co., of Cleveland, Ohio. - The Ptolemaic idea of the Universe
By the second century of the Christian era, the ideas of the early philosophers had become hardened into a definite theory, which, though it appears very incorrect to us to-day, nevertheless demands exceptional notice from the fact that it was everywhere accepted as the true explanation until so late as some four centuries ago. This theory of the universe is known by the name of the Ptolemaic System, because it was first set forth in definite terms by one of the most famous of the astronomers of antiquity, Claudius Ptolemæus Pelusinensis (100–170 a.d.), better known as Ptolemy of Alexandria. In his system the Earth occupied the centre; while around it circled in order outwards the Moon, the planets Mercury and Venus, the Sun, and then the planets Mars, Jupiter, and Saturn. Beyond these again revolved the background of the heaven, upon which it was believed that the stars were fixed— "Stellis ardentibus aptum," as Virgil puts it. - The Rocket 1830
In 1830 all this had disappeared, and we find in Mr. Nasmyth's sketch a regular fire-box, such as is used to this moment. In one word, the Rocket of 1829 is different from the Rocket of 1830 in almost every conceivable respect; and we are driven perforce to the conclusion that the Rocket of 1829 never worked at all on the Liverpool and Manchester Railway; the engine of 1830 was an entirely new engine.