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action, all bear the stamp of careful selection and discriminating judgment. The first volume contains her travels to Rome; the second, her residence in that city, with excursions to the neighbourhood; the third, the journey to Naples and Ischia, with her residence in these places.
"Inquiries into the most important civil affairs, founded on experience. From the English of John Craig Volume I. Jena." The foundations of that policy which is founded on experience, are here exhibited in the German language. This work treats of a most important subject, and gives occasion to serious reflections on political affairs; it is treated with that method which becomes a man of judgment, and by which alone sure results can be obtained. To German readers an introduction by Professor Hegewish will be a welcome accompaniment.
MEMOIRS OF THE PROGRESS OF MANUFACTURES, CHEMISTRY, SCIENCE, AND THE FINE ARTS.
SEVERAL degrees of latitude are
to be measured in Jutland by order of the king of Denmark. The operation will be conducted by Professor Schumusher, who has succeeded the late Mr Bugg as Astronomer
Mr Borie, last spring, examined the Caldbeck fells, in Cumberland, which he found to be principally composed of granite. In some places he observed the granite traversed by veins of quartz, some of them six feet wide, and running N. and S. The quartz, in some veins, is beautifully chrystallized; in others it is intermixed with mica and wolfram. One rein attracted his particular attention. It is five feet wide, runs NNW. and and SSE. and quartz, which is the
predominating ingredient, is associated with crystals of mica, molybdena, and crystals of asparagus stone.
Professor Berzelius was employed last summer, along with Assessor Gahn in examining the minerals in the neighbourhood of Fahlun. The mine of Finbo is in a granite vein, which traverses gniefs. During their examination of this vein, they discovered several new minerals, of which the following are the most remarkable-1. Orthite, so named because it always forms straight radii: it resembles gadolinte, but differs in its fusibility. 2. Neutral fluate of ceruim, crystallized in regular six-sided prisms. 3. Subfluate of ceruim: in it the fluoric acid is combined with twice as much of these bases as in the preceding mineral. 4. Fluate of yttría.
A new printing press, or printing engine, has recently excited the attention of the typographical world.-It is wrought by the power of steam, and, with the aid of two or three boys, perfects nearly a thousand sheets per hour. A common press, worked by two men, takes off but two hundred and fifty impressions on one side, and requires eight hours to perfect a thousand sheets. Hence three boys in one hour, at a cost of six-pence, are enabled, by this new application of the power of steam, to perform the labour of two men for eight bours, at a cost of eight shillings. Such are the present capabilities of this engine; but, as there is no limit to its required powers, and the size of the form is no obstacle to its perfect performance, it is proposed to take impressions on double-demy, in which case three boys, at six-pence, will in one hour, perform the labour of thirty-two men, at sixteen shillings! This engine is now at work at a printing-office near Fleet-street, and another on a similar, but less perfect construction, has, for some time past, been employed on a Morning Newspaper. In its general analogy,
analogy, this press is not unlike the rolling press of copper plate printers. The forms, being fixed on the rriage, are drawn under a cylinder, on which the sheet being laid, and the ink distributed by an arrangement of rollers, the impression is taken on one side. The sheet is then conveyed off by bands to a second cylinder, around which it is carried on the second firm, and the re-iteration is produced in perfect register without the aid of points. All the manual labour is performed by a boy who lays the paper on the first cylinder, by one who takes it off from the second cylinder, and by a third who lays the sheets evenly on the bank. As a farther instance of economy in the materials, we may mention, that the waste steam from the copper is intended to be carried in tubes round the entire suite of offices, with a view to warm them.
The wire-gauze safe-lamp has now been (says Mr Brande) in general use in almost all the northern mines infes ted with fire-damp, for eight months, without a single failure. Sir H. Da vy has lately had some lamps made of thick twilled iron gause, which contains sixteen wires in warp, and about thirty in weft. A single lamp constructed of it never became red-hot in the most explosive atmospheres.Where a very strong light is required in collieries, a large wick may be used, and the cylinder be from 2 to 2.5 inches in diameter.
The following are some of Dr Clarke's experiments with Newman's blowpipe
Vitrification of the Metals of the Earths, and some of the Semi-metals upon Charcoal.-In all the experiments that I have made with the ignited gas where charcoal has been used for a support, this inexplicable property has been more or less mani fested. Pure barytes, mixed with soot
and lamp-oil, and placed within a cavity at the end of a stick of charcoal, instead of exhibiting the dark appearance, which during its fusion denotes its incipient reduction to the metallic state, becomes white, and assumes a vitreous aspect; but when the vitrified mass is taken out of the charcoal, and exposed alone to the ignited gas, fusion ensues, attended with combustion, scintillation, and the revival of the metal. Are we to conclude from this that the base of charcoal is itself metallic? or that the metal is a compound body resulting from the union of hydrogen with the substance which appears to be revived in the metallic state?
Metals of the Earths.-With respect to the metals which I have obtained from silex, barytes, and strontian, and especially from the last two, unless there be a sufficient body of flame, even by means of the ignited gas, they cannot be obtained for want of heat. A tube with too small a diameter, has been the cause of failure in some of my own experiments that were made with a view to the revival of those metals. With Newman's improved blow-pipe, using a wooden screen as a protection, I should consider failure as almost impossible.
Oriental Rubies-Being placed upon charcoal, their fusion was so rapid that I feared they would volatilize.They ran together into a bead, and remained in such a liquid state before the gas, that the current of it penetrated like a stream of air upon oil, when urged by a pair of bellows. The bead, when examined, was white and opake; all colour having disappeared. It was then again exposed to the ignited gas, and being taken from the charcoal, by iron forceps, its surface was covered with a thin flaky metallic substance, which came off upon the fingers, glittering like scales of the carburet of manganese.. Being a third time fused, it assumed a variety
ty of shapes, like sapphire during fusion. As its bulk seemed to be now diminished, the operation was concluded: the bead, when cold, exhibited a pale pink colour; probably owing to a small portion of silex.
Reduction of Tin Oxide.-This affords an easy and very pleasing experiment. Wood-tin exposed to the ig nited gas communicates a beautiful blue colour, like that of violets, to the flame; which, I believe, has not been before noticed. If a pair of iron forceps be used as a support, the iron becomes covered with an oxide of tin of incomparable whiteness. The fusion is rapid; and, if the wood-tin be placed upon charcoal, the metal is revived in a pure and malleable
Reduction of Iron Oxide.-In this experiment, I made use of wood-iron, or fibrous red hæmatite. It was placed upon charcoal, and instantly fused; being reduced to a bead, which began to burn, like iron-wire, by continuance of the heat.
Fusion and Combustion of Platinum.-The largest drops which have fallen from melting platinum wire, when exposed to the utmost heat, weigh ten grains; but we have obtained drops of metal weighing fourteen grains, when the current of gas is diminished so as not to let the metal run off too quickly from the wire: and by placing several globules upon a piece of charcoal, and suffering the whole force of the gas to act upon them, the metal is made to boil, and they all run together into one mass. Semi-metals.—I shall describe some of them as they now appear, more than four months after their reduction to the metallic state :
Cobalt-is a metal somewhat darker than iron, easily admitting the action of a file.
Manganese-resembles the metal of barytes: it is somewhat harder than cobalt, exhibiting a whiter colour, and a greater degree of lustre.
Tungsten or Scheelin.-This metal I obtained from wolfram: it resembles the magnetic iron ore of Lapland, not being, however, itself magnetic. Upon the action of the file it disclo ses a brilliant metallic surface, with high degree of lustre.
Molybdenum-resembles arsenical iron; but when further reduced, and exhibited in the form of globules, it has the whiteness of the purest sil
Uranium-is the hardest of all the semi-metals: the sharpest file will scarcely touch it. The colour and lustre of this metal resemble those of polished iron.
Titanium.-The exterior surface of this beautiful metal, after fusion, is of a black colour, like the metal of barytes when obtained directly from the earth it is very hard. When filed it is nearly as white as silver.
Cerium. The appearance of this metal is like that of iron it is very hard, and its surface, after fusion, is of a brownish colour.
Plan for a Line of Canal upon One Level, between the Cities of EDINBURGH & GLASGOW. By ROBERT STEVENSON, Esq. Civil Engineer.
THE plan of a canal to unite Edin
burgh and Glasgow has, for some time past, excited the greatest possible interest. The comparative merits of the Level Canal, recommended by Mr Rennie, and of the Union Canal by Mr Telford, have been a subject of very eager discussion. Here, however, we have the proposition of a new line, which holds out advantages superior to those afforded by either, though accompanied with some difficulties peculiar to itself. This line, proposed by Mr Stevenson, an engineer of the most acknowledged eminence, presents the remarkable feature of forming a navigable communication
between these two great cities without a single lock. He thus proposes to save at once the original expense of constructing the locks, the difficulty of procuring water, and the inconveniences to which they subject boats and passengers. Another very important advantage is the facility afforded in carrying the canal down to Leith, as his proposed level is from 80 to 120 feet lower, than that of any of the other lines of canal. The modes in which the canal may be locked down to Leith appears to have occupied much of Mr Stevenson's attention; and he observes
It may here be mentioned, that from the almost complete occupation by buildings, of the lands between Edinburgh and Leith, it is rendered a matter of considerable difficulty, to find a track between the City and its Port, that shall be direct, without in terfering with valuable property.One line, from Edinburgh to Leith, sets off from the Hay-market at the west end of Maitland Street, and locks down by Canonmills to the Wet Docks, as delineated on the plan. This line would admit of a Wharf being formed at Canonmills, from which the communication with Leith might be made by only three or four locks; an important view of the case, which, in effect, might be conceived as extending the Harbour of Leith to the very skirts of the City of Edinburgh. A second line of direction to Leith, and capable of forming a similar, or even a closer connection between the City and its Port, although it is not quite so direct, and may appear at first sight intricate, will perhaps upon the whole be found fully as eligible. This line may begin to lock down to Leith from a Basin at the North Bridge; passing under the Centre Arch, and along the southern side of the Old Physic Gardens, and back grounds on the southern side of Paul's Work, and adjoining properties, as shewn upon the plan, to the
Abbey-Hill, and along the Eastern Road to Leith; through the Links of Leith to the glass Works, where the line may turn westward at high water-mark, and be made to enter the Harbour of Leith opposite to the Gates of the Wet Docks,―by a work, which, though somewhat expensive, may with great propriety be considered as subservient to the acquirement of much valuable property, by the formation of an extensive Basin and Wharf walls along the South Sands, bringing important advantages to the Trade of Leith.'
He afterwards describes as follows the line by which the canal is to pass :
In tracing this extensive level, as delineated and shown upon the accompanying plan, it proceeds from the site of a Basin opposite to Canal Street, westward, and may be made to pass along the sloping bank on either side, or the middle of the North Loch grounds, and be tunnelled through the Earthen Mound. It then crosses the road leading to the West Church near by the Castle Rock. From thence it keeps a westterly direction; crossing the Lothian Road, it passes through the hollow ground on the southern side of Maitland Street; crosses the public road at the Hay-market, and again at Tyne-castle Toll-bar. It then passes, on the southern side of Gorgie Mills, to the Water of Leith, at Stenhouse Mills, north of the village of Slateford, and proceeds westward, on the northern side of the Hailes Quarry and Saughton; reaches the River AÍmond, and crosses it, below Bird's Mill. The line of direction still continuing westward, meets with the village of Broxburn, when it turns to the north-west in the direction of Three Mile Town to near the village of Pardovan, or it may here be carried more to the westward, and made to enter a flat tract of country, and then turn westward in the direction of the Long Erricburn, terminating
in the Basin at the east end of the Town of Linlithgow. The line then winds round the northern side of Linlithgow Loch, and reaches the River Avon, which it crosses about a mile and a half below, or to the northward of Linlithgow Bridge; it then crosses the Edinburgh Road near the four mile stone. Continuing westward, it passes on the southern side of the village of Polmont, and north era side of the village of Redding, and reaches the Haw Glen and Bridge, on the road leading to Shielhill. It then takes a northern direction, to wards the Basin for the Town of Falkirk, and again turns to the west ward, and passes upon the southern side of Glenfuir, and northern side of Castlecary, to Lock 20, where it forms a junction with the Forth and Clyde Canal, and is continued, by that navigation, upon the same level to Port Dundas; from which it may be locked down to the Broomielaw and River Clyde, by fourteen locks, of 11 feet 2 inches each.
'From Port Dundas the line crosses the public road at the village of Cowcaddens, and is continued by a short tannel, in a direct line through the Observatory Hill to the low grounds of Blytheswood. After this a convenient line is found through vacant grounds to Smithfield, at the Broomielaw, near which it terminates in the River Clyde, at the Tonnage Office.
whence Canal vessels could proceed to Paisley, and through Ayrshire, by the Ardrossan Canal. But still, great advantages would attend the connection of Port Dundas by water with the Clyde at the Broomielaw. This new Junction Line would thereby communicate with the Frith of Forth at Leith, the Forth and Clyde Canal at Lock 20, the Monkland Canal at Port Dundas, and also with the River Clyde, and Ardrossan Canal; and would thus form a Junction Canal of the greatest commercial importance to this part of the kingdom.'
'The reporter is aware that this cut or branch, from Port Dundas to the Clyde at the Broomielaw, may be objected to on account of the expence, estimated at £.59,933, 18, for one mile of navigation, while the land-carrage from the Broomielaw to Port Dundas is only about one mile and a quarter; especially as the Forth and Clyde Canal, with which this level line forms a junction, communicates with the Clyde at Bowling Bay, and may be very easily locked down to the Clyde (as has been suggested) opposite to the River Cart; from February 1817.
This line, therefore, is evidently preferable to all others proposed, in every respect except one, which is, that it requires the excavation of two tunnels, one of which is three miles in length. The expense, which is estimated at £.132,000 for the larger, and £.43,000 for the smaller one, is not the only objection to such a mode of preserving the level. So long a passage through this region of subterranean gloom, with the dread of what might descend from above, would, it is supposed, deter boats, and especially passengers, from adventuring by such a track. It is but fair, however, to listen to what Mr Stevenson urges, in order to dispel the public apprehension on this subject:
Although the operation of Canal tunnelling is rather a novelty in Scotland, such works are by no means uncommon in England, of an equal or greater extent than that now projected. There, no ideas of fear or apprehension are connected with them; and it is with great probability supposed, that, were such a navigation as that now proposed opened but for a few months, the Broxburn Tunnel would be passed with as little concern as any other part of the line.
It may here be noticed, that the tunnelling upon this line of Canal is proposed to be very differently finished from works of this kind intended merely for mining operations, or the