OCCASIONAL NOTES.

TELEGRAPH EXTENSION.

The scheme for the extension of the telegraph system, in anticipation of the meditated introduction of the sixpence rate, is a most comprehensive one, and indicates that the Post-office authorities anticipate a very considerable increase of work. The arrangements cover the entire kingdom, and the sum to be expended is half a million, part of the sum having been voted in the official year 1883-84, and the remainder to be voted in the new estimates. From London, upwards of eighty new wires are to be erected to the principal towns of the kingdom, including four additional wires to Liverpool; two each to Birmingham, Manchester, Leeds, Newcastle, and Newmarket; three to Glasgow; two to Edinburgh; and one each to a large number of towns, including, in Scotland, Aberdeen and Dundee. Within London itself, five new pneumatic tubes are to be provided; about seventy new wires will be erected; forty existing wires will be provided with instruments to work ‘duplex’—that is, with the power of transmitting two different messages by one wire from each end simultaneously; and a very large number of offices will have simple apparatus substituted by other and improved instruments. In the city of Liverpool, in addition to the London wires named, three new wires to Manchester are to be put up; and one new wire to Belfast, Birmingham, Blackburn, Bristol, Carlisle, Glasgow, Hull, Leeds, and Newcastle. All those wires and all the new London wires are to be ‘duplexed,’ and thus each new line practically counts as two. A number of wires out of Liverpool and the other large towns will be converted to duplex; and Liverpool is to have eight new pneumatic tubes for its busier local offices. At Manchester, besides the London and Liverpool communications already named, there will be new wires to Birmingham, Chester, Edinburgh, Leeds, Newcastle, Bolton, Burnley, Derby, Huddersfield, Hull, Isle of Man, and Nottingham, all duplexed. At Newcastle, an evidence of the curious ramifications of trade is seen in the fact that a new wire is to be put up between that town and Cardiff. Bristol obtains new wires to London, Liverpool, Birmingham, Swansea, and Cardiff; and a share of a new wire for news purposes with Exeter, Plymouth, &c. Sheffield in the same way has a new wire to London, and a share in a news circuit with Nottingham, Leeds, and Bradford. At Birmingham, a number of new local wires, and the duplexing of others, are provided in addition to the various new trunk wires already named. In Scotland, a considerable number of new wires fall to be erected. Edinburgh obtains two of the new London wires, and wires to Manchester, Kelso, and Musselburgh, with the duplexing of some important wires, such as those to Kirkcaldy and Perth. Glasgow, with three London wires added, gets new wires to Dundee, Leeds, Liverpool, Oban, Kilmarnock, Falkirk, &c.; while a large number of the existing wires will be duplexed, and in some cases re-arranged to give more suitable service. A considerable number of new local wires are to be erected in both cities. In Aberdeen, besides the new London wire, the principal change will be new wires to Wick and Lerwick—the last a most important improvement, as Shetland messages will reach London with two steps, instead of being, as now, repeated at Wick, Inverness, and Edinburgh or Glasgow.

We observe that the French are about to increase enormously their telegraphic system, and that the new wires are to be laid underground. It would be well if, remembering the ever-recurring havoc wrought upon our overhead wires by gales and snow, we followed the example of our Gallic neighbours.

AN OIL BREAKWATER AT FOLKESTONE.

A series of experiments has been made at Folkestone, with the result of very satisfactorily demonstrating the value of the method of spreading oil over troubled waters which has been devised by Mr John Shields, of Perth, and which has been already described in this Journal. Many years ago, Mr Shields, observing the effect of a few drops of oil accidentally spilt on a pond in connection with his works, began experiments with a view to determine if this property of oil could not be turned to account on a large scale for the saving of life and property at sea and on our coasts. He soon arrived at the conclusion that the problem to be solved was ‘how to get the oil on troubled waters when it was wanted and where it was wanted.’ By trying various methods of solving this question, first at Peterhead and then at Aberdeen, he has worked out the system which, with the co-operation of the South-eastern Railway Company, has at his expense been placed in readiness for use during stormy weather off the entrance to the harbour at Folkestone.

On the 29th January, Mr A. Shields, son of the inventor, and Mr Gordon, of Dundee, carried out a number of experiments at Folkestone before a distinguished company. The weather, unfortunately, was not all that could be desired; it was too moderate, and the wind blowing from the west did not drive such breakers across the harbour bar as a strong south-wester would have produced. Nevertheless, the channel near shore was sufficiently rough to prove the efficiency of Mr Shields’ arrangements for smoothing it. What was seen by the visitors may be told in few words. Three large casks were lying on their sides near the pier-end, and pipes inserted in these were connected with small force-pumps, each worked by a man. Attention was first directed to windward towards the unfinished new pier, which juts out to the south-west. Those who have watched these experiments on former occasions said they could see the oil rising from a submerged pipe laid from the old pier-head towards the new pier for a distance of five hundred feet. The flood-tide, however, was running so strongly that it was not until the oil had passed the pier that its effects began to be visible, and these effects were soon more distinctly seen as the two men stationed at the other barrels began to pump oil into a couple of pipes, also laid on the sea-bottom, and running across the entrance of the harbour towards Shakspeare’s Cliff for about one thousand yards. A fully-manned lifeboat, the Mayer de Rothschild, had been rowed out of the harbour, and was lying off the pier-head, rolling a good deal, but not getting a splash while in the wide glassy strip of oil-covered waters that soon stretched away for half a mile or more, though to seaward of this glistening streak the waves were curling and breaking into foam. On the harbour-side the effects of the oil were noticeable far in-shore, and few white caps were to be seen, the film, attenuated as it must have been, and not more than one hundred feet in width, acting apparently as an efficient breakwater. When the pumping was stopped, it was estimated that rather over one hundred gallons of oil had been used.

The trial, which was as satisfactory as the conditions of weather permitted, was concluded about one o’clock; yet at four, when the Boulogne boat came in, broad streaks of comparatively smooth, unbroken water showed where the oil still lay on the surface. For this permanent apparatus, lead-pipes of about one and a quarter inch diameter are used, and at distances of one hundred feet apart there are fixed upright pipes eighteen inches high, in each of which is a conical valve, protected from silt by a rose. The oil used was seal-oil, some kind of so-called fish-oil having been found by experiment to be better for the purpose than either vegetable or mineral oils.

A second experiment was made at the same place with Mr Gordon’s invention. This consists of firing shells filled with oil, which, when the shells burst, spreads itself over the water. Each shell contains about three-quarters of a gallon of oil. They are fired from mortars, a charge of eight ounces of pebble powder being used. The shell is simply an oil-flask, at the bottom of which is a recess for a fuse of somewhat peculiar construction. It consists of two small chambers. In these there is a projecting submarine fuse about an inch in length. The fuse is capped with a composition which renders it absolutely waterproof, and is so constructed as to secure its ignition with unfailing certainty. Then the fuse is so timed that it bursts at the time required, and just as the shell is touching the surface of the water. The oil from each shell covers a very considerable area of surface. Somewhere about a dozen of these shells were fired at a range of from four hundred and fifty to five hundred yards. The effect was wonderful. The hissing and raging waters were gradually allayed. For a considerable space the sea was converted into a lake with a gentle swell, in which a ship or a boat could ride with perfect ease. The shells, of course, obviate the necessity of pipes, and the smallest seaport in the kingdom might therefore, with an old mortar and a dozen or two of gallons of oil, make a temporary harbour of refuge whenever the necessity arose.