I presume that it was under the pressure of feelings occasioned by this state of things, that Mr. Bernhard Weymouth (one of the chief surveyors of "Lloyd's Register"), when attending before the Megæra Commission to give evidence, took the first opportunity which the question put to him afforded, of having a dig at those ship-owners who do not patronise his committee or their surveyors.

Sir Frederick Arrow asks Mr. Weymouth: "Is there any such stringent examination of Government ships as would lead to the confidence which is felt with regard to the Mercantile Marine, owing to the surveys made under your authority?"

"No" (says Mr. Weymouth), " and I am sorry to say that I think the same answer applies to vessels belonging to large companies as much as to those in the service."

Now, I would ask your readers whether a more unjustifiable and unfounded attack was ever made upon the best part of the great Mercantile Marine of this country. The suggestion is two-fold: 1st. That there is an absence of confidence felt in the vessels of those large companies which do not submit themselves to "Lloyd's Register;" 2nd. That there is no proper examination of such vessels.

What are the facts? Let me enumerate a few, and only a few, of the of the large companies who do not patronise "Lloyd's Book."

The Peninsular and Oriental Company, the Royal Mail Company, the whole of the great Atlantic lines, sailing from Liverpool (viz., Cunard, Inman, Allan, Guion National Anchor line of Glasgow, and Oceanic Companies), the Pacific Steam Navigation Company, and Lamport and Holt's line are specimens of the "large companies referred to." Can Mr. Weymouth tell us whether the public feel a want of confidence in the steamers of those lines? Do passengers refuse to embark in them? Do her Majesty's Government refuse to despatch mails by them? Do shippers refuse to ship by them, or do underwriters refuse to take risks on them at low rates until they submit themselves to the jurisdiction of Lloyd's surveyors, and put down their names for a copy of "Lloyd's Book ?" I should like to know whether the confidence felt by the mercantile world and the general public in the steamers belonging to those undertakings is not far greater than the confidence felt in the certificates of Lloyd's surveyors, and whether it is not shown by experience to be fully justified.

I should like to know whether it would add anything to that confidence, or to the safety of the vessels forming the vast fleet owned by those great lines, if Lloyd's surveyors were to superintend the building of such vessels, or survey them periodically.

To come to the second point: does Mr. Weymouth not know that there are examinations of these vessels regularly made quite as stringent as any he or his co-surveyors could institute, and by persons quite as

competent. I presume that he has heard of the Board of Trade Surveyors with their half-yearly surveys, and the Emigration Surveyors (for vessels coming under Passenger Acts) with their surveys every voyage. But putting aside the Government officials, does he not think that the owners of vessels-each vessel costing, perhaps £100,000 or £120,000, and carrying, perhaps, 1,000 passengers and 2,000 tons of cargo at a timeowners whose very existence as great carriers of goods and passengers (keenly opposed as they are by their competitors) depends upon their reputation and their freedom from breakdowns, accidents, or mishaps of any kind, exercise no superintendence over their vessels, and have no skilled superintendent, engineers, or competent surveyors of any kind, to keep a watchful eye upon every ship belonging to their fleet?

Lloyd's do not like to confess it, but the fact is, that not only in regard to the large lines, but also in regard to iron vessels generally, "Lloyd's Register" is falling into the rear. The Liverpool Red Book, or "Underwriters' Registry for Iron Vessels," is supported by surveyors quite as competent as those attached to "Lloyd's Register," and the former book is more valuable and complete than the latter with regard to such vessels, and held in higher estimation by underwriters and the mercantile public generally. But the surveyors to that Book are not so foolish as to expect the great companies, who have their own superintendent engineers, and whose well-earned reputation is their best certificate, to submit their vessels to the surveys of the Iron Registry. And those surveyors would, we venture to say, be the last to support the statement made by Mr. Weymouth, to which we have referred above. They would not be disposed to suggest in public before a committee of gentlemen, who probably do not know the real facts, that the mercantile world do not feel any confidence in the vessels of such companies, and that due and proper precautions are not taken to ensure their seaworthiness and safety.

BLUE MOUNTAIN.

GAS WORKS FOR SHIPS AND LIGHTHOUSES.

THE vast superiority of gas over all other known means of artificial illumination for its efficiency, safety and economy, will, we think, be admitted by all.

The ordinary mode of making gas, however, has rendered its use for ships or lighthouses next to impossible, except in a few cases for the latter. We are happy now to be able to state that this great want is likely to be met, by the introduction of thoroughly good and efficient Portable Gas Works.*

Mesars. J. ALLAN and Co., 64, Cumberland Street, Calton, Glasgow, or 23, St. Enoch Square.

The above woodcut represents an apparatus specially adapted for ships. It has, we learn, been in use for a considerable time, at the works of Messrs Allan, in Glasgow, with the most satisfactory results. They use, we have ascertained, the best Lesmahage cannel coal, from which they state that they can obtain upwards of 14,000 cubic feet per ton of 38 to 40 candles illuminating power. With the little apparatus figured above, they can make 960 cubic feet of gas in 24 hours continuous making. This represents a light equal to an average of 312 standard sperm candles an hour for 24 hours, or an average of 413 per hour for 18 hours. The cost would appear to be not more than 2/3 per day, not including labour, but this is a very small item as we shall see presently.

The space the apparatus occupies is very small. The stove, or generator, is in breadth 21 by 27 inches, and the height, including the moveable top, is 7 feet. The condenser, with purifier on the top, is 2 feet by 3 feet 4 inches. The gasholder is 5 by 7 feet, outside measurement, and can be placed anywhere, and made to any shape. The retort used by Messrs. Allan, which is cylindrical, is placed in a vertical position, surrounded by a fire-clay jacket 3 inches thick, with a free space of 1 inches between it and the retort all round, for the smoke and flame of the furnace below. There is an iron covering surrounding the jacket, with an inch of free space for ventilation and for the prevention of unnecessary

heat. The top of the retort and the lid are engine-turned, making an air-tight joint, and thus dispensing with the use of soft lime or clay when charging. When charging the retort, the upper part of the stove is thrown up, as shown in our woodcut, and an iron cage, previously filled with gas coal (which exactly fills the cavity of retort), is dropped in. The lid is then pushed back, and locked down by a lever. The whole operation of charging can be done in thirty seconds, and without inconvenience from smoke or dust. The condenser effectually condenses the grosser parts of the gases in the shape of tar and ammoniacal liquor, and discharges them into the tar-well. This arrangement, in fact, forms the speciality of Messrs. Allan's apparatus, and makes all the rest possible for a ship. The hydraulic main, and in fact all water in the process of manufacture, are dispensed with. The purifier is a circular iron vessel, containing a series of sieves filled with sawdust, sand (of a particular kind), and lime, through which the gas percolates, entering by a pipe below from the condenser, after which it passes into the gasholder, which is a collapsible bag, with a wooden top and bottom and cloth sides. The cloth is made specially for the purpose, and is, as far as we can ascertain, perfectly gas-tight and very strong.

There is, so far as our inquiries have enabled us to investigate, really no danger in working this apparatus on board ship, unless from deliberate malice or design. The only apparent danger would be that arising from any omission to open or shut the valve on top of condenser when charging; but supposing this omission to occur, we could not discover that anything more serious would happen in the first place than the loss of a few feet of gas, which would ignite and flow harmlessly up the funnel; or, in the latter case, than that the gas in the retort would open the valve when it reached a pressure of about 2 lbs.

On the whole, we are much pleased with the apparatus, and trust that our large shipowners may be able speedily to make practical use of it. Next to its efficiency one important thing in its favour is its price, which Messrs. Allan, in reply to an inquiry on the point, inform us is, " £45, f. o. b., at Glasgow,"-whatever that may

mean.

CAPTAIN EVANS, R.N., F.R.S., ON COMPASS DEVIATION.

A LECTURE on the "Present state of our knowledge respecting the Magnetism of Iron Ships, and the treatment of their Compasses," was given at the Royal United Service Institution, on Friday, the 2nd February last, by Staff-Captain Frederick J. Evans, R.N., F.R.S., Chief Naval Assistant in the Hydrographic Department of the Admiralty. The meeting was presided over by General Sir Edward Sabine, K.C.B., late President of the Royal Society, so well known in magnetic science; and was attended by many naval and military officers, and gentlemen interested in science and education.

The aim of the lecturer was to convey to the members of the Institution the progress of knowledge made within the last twenty years relating to the magnetism of iron ships, the treatment of their compasses, and the consequent security of their navigation. This period was chosen, as in the year 1852 the late Dr. Scoresby, in the same theatre, had delivered a lecture, which greatly influenced the minds of the seamen of the day— on the insecurity of the navigation of iron ships, resulting from the system then gradually being introduced into the mercantile marine, of correcting the deviation of ships' compasses by permanent magnets. This system he considered to be opposed to correct principles.

After ample recognition of Scoresby's labours in his cherished branch of science, and his sagacious elucidation of many laws now fully confirmed by more extended experience; it is shown in the lecture that those principles which he had set forth as to the insecurity resulting from magnet correction-based, it is believed, much on the reports of otherswere not justified, except when the teachings of science had been neglected or evaded.

Attention was here directed to two papers on the same subject, which the lecturer had read to the Institution in 1859 and 1865 (and printed in its journals) in order to avoid undue repetition. These papers treated in some detail the varied theoretical considerations of the magnetism of iron and especially iron-clad ships; directed attention to the experiments and investigations of the Astronomer Royal, made in 1838-9, on the iron ships Rainbow and Ironsides; to the labours of the Liverpool Compass Committee in 1855-61; and to the mathematical investigations and formulæ of Archibald Smith, Esq., to be found in the Admiralty Compass

Manual.

In calling attention to the present state of our knowledge, the lecturer dwelt strongly on its true foundation being the mathematical treatment. This treatment,originally designed by the eminent French philosopher, Poisson, and successively developed by the investigations, on a practical basis, of the Astronomer Royal, and by those of Mr. Archibald Smith, who dealt with the actual problem on the footing of Poisson's equations; is now reduced to forms admitting of immediate practical use, and bearing their own physical interpretation on their face.

The lecturer considered that to a comparatively recent date this mathematical treatment of the iron ship's magnetism had scarcely commanded the confidence of the naval profession; that seamen appeared either to fail in appreciating the true value of a scientific mode of treatment, or, hoping that some short road might be discovered, involving no labour or science to follow out, trusted to that alternative for the practical working of the mariner's compass being settled. These popular fallacies are deemed unsound, and prone to do. harm, especially as the formule