An important patented process for producing tapered iron, has been explained before the Franklin Institute at Philadelphia—one by which every variety of taper may be produced, or combinations of taper, with flat or other forms; and seeing how much tapered iron is used on railways, in many kinds of machinery, in ships and steamers, the subject may be considered worthy of more than a mere passing notice. Tapered iron is a form to which machinery has been thought inapplicable, and only to be produced by hand-labour. The new method, however, which has been successfully carried into practice at the Phœnixville Ironworks, is thus described: 'The principle on which it acts is that of hydrostatic pressure, or, more properly, hydrostatic resistance. A small chamber, similar to that of the common hydrostatic press, is set on the top of each housing; the closed end of the press being uppermost, and a plunger entering from below; but instead of water being forced into the press, the chamber is at first filled with water, and the pressure of the iron in passing between the rollers, tends to lift the top one, which is held down by the plunger. An escape-pipe, provided with a valve, is inserted into the top of the chamber. When any upward pressure acts on the top roller, it is communicated by the plunger to the water, which escapes through the valve, and the roller rises.

'When the valve is partially closed, the water escapes more slowly; and the rise of the roller, and consequently the taper of the iron, are more gradual.

'Any rate of taper may thus be had by regulating the rise of the opening of the escape-valve. If the water is all driven out before the bar is entirely through the rollers, the top roller ceases to rise, and the iron becomes parallel from that point. Then, if the ends of the bar be reversed, and it be again passed between the rollers, the parallel portion will become tapered; thus we can get a bar.'

At the same time, a 'Thermometrical Ventilator' was exhibited, which is described as circular in form, with a well-balanced movable plate. 'Upon the side of the valve is an inverted syphon, with a bulb at one end, the other being open; the lower part of the tube contains mercury; the bulb, atmospheric air. An increase of temperature expands the air in the bulb, drives the mercury down one side and up the other, thereby destroying the balance, and causing the valve to open by turning on its axis. A diminution of temperature contracts the air in the bulb, causes the mercury to rise in the side of the tube, and closes the valve.' Besides this, there was 'an improved magneto-electric machine, for medical use, with a new arrangement, by which the shock is graduated by means of a glass tube, in which a wire is made to communicate with water, so as to produce at first a slight shock; by gradually pressing down the wire attached to a spiral spring, the shock is received in its full force.'

It now appears that Mr Robertson of Brighton claims priority of discovery touching the boring power of Pholades. His statements are founded on daily observation of the creatures at work for three months. 'The Pholas dactylus' he says, 'makes its hole by grating the chalk with its rasp-like valves, licking it up, when pulverised, with its foot, forcing it up through its principal or bronchial syphon, and squirting it out in oblong nodules. The crypt protects the Pholas from confervæ, which, when they get at it, grow not merely outside, but even within the lips of the valves, preventing the action of the syphons. In the foot there is a gelatinous spring or style, which, even when taken out, has great elasticity, and which seems the mainspring of the motions of the Pholas dactylus.'

At last, steam communication with Australia seems about to become a reality, for the first vessel is announced to start in May for Sydney, to touch at the Cape and other colonies on her way out; and accommodation is promised for two hundred passengers of different classes. There is also a project on foot for a line of steamers from Panama to Australia, and to Valparaiso, which, if brought into operation, will make a voyage round the world little more than a bagman's journey. Apropos of Australia, Mr Clarke, who first predicted that gold would be found in that country, says, 'that just 90 degrees west of the auriferous range in Australia, we find an auriferous band in the Urals; and just 90 degrees west of the Urals, occur the auriferous mountains of California.' A speculation for cosmogonists. In our own country, we are finding metalliferous deposits: vast accumulations of lead-ore have come to light in Wales, which are said to contain six ounces of silver, and fifteen hundredweight of lead to the ton; and in Northamptonshire, an abundant and timely supply of iron-ore has just been met with. We might perhaps turn our metallic treasures to still better account, if some one would only set to work and win the prize offered by Louis Napoleon; namely, 'a reward of 50,000 francs to such person as shall render the voltaic pile applicable, with economy, to manufactures, as a source of heat, or to lighting, or chemistry, or mechanics, or practical medicine.' The offer is to be kept open for five years, to allow full time for experiment, and people of all nations have leave to compete. One of the electric telegraph companies intends to ask parliament to abolish the present monopoly as regards the despatch of messages; in another quarter, an under-sea telegraph to Ostend is talked about, with a view to communicate with Belgium independently of France; and there is no reason why it should not be laid down, for the Dover and Calais line is paying satisfactorily. And, finally, another ship-load of 'marbles' and sculptures has just arrived from Nineveh; and the appointment of Mr Layard as Under-Secretary for Foreign Affairs (though now but temporary) is regarded as a praiseworthy recognition of his merits and services; and now that we have a government which combines a few littérateurs among its members, it is thought that literature will be relieved of some of its trammels.

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