Altogether, the book is sweet, fresh, tender-hearted, like a whiff of the foaming ocean spray, quite out of the hackneyed round, and yet sufficiently realistic to impress the reader with a conviction that it is the record of a life which has been lived, which, if not the highest aim of the novelist's art, is yet an indispensable adjunct to it. We have only to add that Shetland is now easily reached by regular steamers plying between Granton (Edinburgh) and Lerwick, the capital of the islands; while we believe a small steamer plies from Lerwick for local accommodation. A summer cruise in a yacht would, however, be the perfection of voyaging for the purpose not only of seeing Shetland, but Orkney and various intermediate islands, such as Fair Isle and Foula, which are out of the way of general traffic. To visit these distant fragments of land in the north, forming the scene of Scott's vivid romance of The Pirate, would furnish a new sensation never to be forgotten.
[THE MONTH:]
SCIENCE AND ARTS.
The Report of the meeting of the British Association held last year at Glasgow has just been published in a goodly volume of more than three hundred pages. Among its contents are Reports of Committees, of which it may be said that the more widely they are known the better; and bearing in mind recent disasters at sea, the Investigation of the Steering Qualities of Ships by Professor Osborne Reynolds of Owens College, Manchester, appears the more interesting. 'The experiments of the Committee on large ships,' he remarks, 'have completely established the fact, that the reversing of the screw of a vessel with full way on, very much diminishes her steering power, and reverses what little it leaves; so that where a collision is imminent, to reverse the screw and use the rudder as if the ship would answer to it in the usual manner, is a certain way of bringing about the collision.' This is an important fact, for it is well known that collisions have been occasioned by the very means made use of to avoid them. And Professor Reynolds says further: 'It appears that a ship will turn faster, and for an angle of thirty degrees, in less room when driving full speed ahead, than with her engines reversed, even if the rudder is rightly used. Thus when an obstacle is too near to admit of stopping the ship, then the only chance is to keep the engines on full speed ahead, and so give the rudder an opportunity of doing its work. These general laws are of the greatest importance, but they apply in different degrees to different ships; and each commander should determine for himself how his ship will behave.... It is also highly important that the effect of the reversal of the screw should be generally recognised, particularly in the law courts; for in the present state of opinion on the subject, there can be no doubt that judgment would go against any commander who had steamed on ahead, knowing that by so doing he had the best chance of avoiding a collision.'
The statements thus set forth are illustrated by diagrams which shew the position of the vessel after reversal of the screw, and the position after steaming ahead. The latter shews that collision would be entirely avoided.
We frequently read that in future sea-fights the ram will be relied on for running down enemy's ships and sending them to the bottom. But where is the captain at the present day who has had experience of ramming, and of other evolutions which will be required in a fleet of steam ironclads under quite new conditions? Soldiers can go into temporary camps and get experience in 'autumn manœuvres;' but sailors cannot have mock-actions and run down ships which cost half a million sterling, nor venture to try the eighty-ton-gun on their consorts. Hence there will be very much to learn in the first great naval battle.
Under these circumstances, Professor Reynolds recommends that small steam-launches should be built of wood, each representing the exact form of one of our large ships, and that with these all possible manœuvres should be carried out, and officers make themselves familiar with all the effects of the screw on the rudder, with all the conditions of steering, with all the evolutions requisite to bring about or to avoid a collision, and with the effects of ramming. If strongly built of wood, these little vessels would withstand an experimental blow from the ram.
The value of such experiments would be real, for it is now known that the behaviour of a small copy of a ship is exactly the same as that of the great ship, in proportion to the size. The waves set up by the launch bear the same relation to her size as the waves of the ship do to the ship. The recognition of this law marks an epoch in the progress of naval architecture. Given a model, Mr Froude 'can now predict with certainty the comparative and actual resistance of ships before they are constructed.'
The Report of the Committee for investigating the circulation of the underground waters in the New Red Sandstone and Permian formations of England, and the quantity and character of the water supplied to various towns and districts from these formations, conveys information interesting to everybody—for everybody drinks. At Liverpool there are wells sunk in the New Red Sandstone which yield more than seven million gallons daily; at Birkenhead the same; at Coventry, Birmingham, and Leamington four millions and a half; at Nottingham nearly four millions; and at Warrington and Stockport more than a million and a half gallons every day. The total makes up a large quantity; but it is nothing in comparison with the supply which the whole area of the New Red may be expected to furnish. This area, says the Report, is certainly not less than ten thousand square miles in extent in England and Wales, with an average rainfall of thirty inches, of which certainly never less than ten inches per annum percolates the ground, which would give an absorption of water amounting to no less than one hundred and forty-three millions three hundred and thirty-six thousand gallons per square mile per annum; which, on an available area of ten thousand square miles, gives an annual absorption of nearly a billion and a half of gallons in England and Wales. As if to heighten the effect of this good news, we are told the 'New Red Sandstone Rock constitutes one of the most effective filtering media known.... It exerts a powerful oxidising influence on the dissolved organic matter, which percolates it to such an extent, that in the waters of certain deep wells, every trace of organic matters is converted into innocuous mineral compounds.' And again: 'Waters drawn from deep wells in the New Red Sandstone are almost invariably clear, sparkling, and palatable, and are among the best and most wholesome waters for domestic supply in Great Britain.' After reading this, may we not say that Undermere, about which no one will quarrel, is the lake whence great towns in the north should draw their water supply?
During the meeting of the British Association at Plymouth last August, the Mineralogical Society held their second annual gathering under the presidency of Mr Sorby, F.R.S., who in his address gave an account of a new method for determining the index of refraction of minerals, which can be readily employed in their identification. This seems a dry subject; but it is one likely to be valuable and interesting to mineralogists and chemists, and to lead to an entirely new branch of mineralogical study, and to the discovery of a new class of optical properties of crystals. For a proper understanding of the method, a knowledge of optics, of mathematics, and other branches of science would be necessary; but we may state generally that it is based on the fact, that if an object, when placed in focus for examination on the stage of a microscope, is covered with a plate of some highly refracting substance, the focal length is increased; in other words, the microscope must be raised a little farther from the object in order to restore the focus. The distance to which the microscope has been moved thus becomes a measure, which can be accurately determined on a scale to thousandths of an inch. By this measure, therefore, very minute differences of refraction can be determined, and the several minerals identified; and Mr Sorby, in conjunction with Professor Stokes, Sec. R.S., has arrived at certain definite conclusions, which, embodied in numerical tables, may ere long be consulted by all interested in the subject.