could be shown that the ordinary precautions had been taken at the port of shipment of the cargo," and goes on to say that "the law relating to the stowage of grain must be amended," and that "if responsibility is to be forced on shipmasters and shipowners. there must be at all events some definite rules for their guidance," and our contemporary goes on to point out the direction these rules should take, saying "the remedy for the existing evil and danger will be, not merely in stowage rules however stringent, but in rules relating to the proportions and construction of sea-going ships," and it hints at the question whether Parliament may possibly make such rules.

We know nothing of the complete agreement said to exist between the Board of Trade and the shippers of grain as to not prosecuting in cases when the existing law is broken. But we do hope, in the interests of all parties, that the treaty or understanding, whatever it is, between the Board of Trade and the shipowners as to "ordinary" precautions, only refers, if it exists at all, to "ordinary" ships. For the Board of Trade to undertake that it will not prosecute if the law is broken when "ordinary" precautions are taken in ships which require "extraordinary" precautions to ensure even a common amount of safety, seems to us so strange that we cannot and do not credit it.

We look, however, with great alarm on the proposal of our contemporary as to statutory provisions, concerning stowage rules, however stringent, and rules as to the proportion and construction of ships. This is out-Plimsolling Plimsoll; Mr. Plimsoll only proposed that all ships should be driven compulsorily into classification, but seeing that most of the missing ships were classed and bore very high characters, he may perhaps be now convinced that even his comparatively mild remedy would not have affected the question of safety. We told him so at the time, and we trust he sees it

now.

Our contemporary thinks, however, that the time has come for inquiry into the causes of loss of ships carrying grain. But surely he overlooks the fact that inquiry is held in case after case by the Wreck Inquiry Courts! One would think that there is inquiry enough already. If, however, our excellent contemporary means

that to be of use in lessening loss of life, inquiry should be of another sort, then we are not indisposed to agree in the conclusion at which he has arrived, that the "losses have reached a point at which inquiry has become imperative, with a view to ascertaining how these recurring sacrifices of life and property may be best prevented." We have remarked on more than one occasion that the results of the inquiries of the Wreck Court produce little or no effect on the mass of constructors, designers, owners, masters, and loaders of ships. They punish officers, it is true, but that is a very poor result to the British taxpayer as compared with their assumed importance and great cost. We are not blaming the framers of the reports of the Wreck Court; it is not their fault that their reports do not bear the desired fruit. Legislation of the strait-jacket order may be useless or mischievous; extended inquiry can alone decide that it shall not be.

WATER BALLAST AND GRAIN CARGOES.

(Communicated.)

HE recent unfortunate losses of grain-laden steamers in the Atlantic have been the cause of the revival of a question which was the subject cf much debate a few years ago, when a larger number of similar losses

occurred in quick succession. As the vessels in recent cases nad the water ballast tanks which are so common now in new steamers, it has been alleged that water ballast, as well as the carriage of grain in bulk, is a source of special and peculiar danger. It is stated that during the next session further legislation will be proposed, prohibiting the carriage of grain otherwise than in bags. We have not yet heard, however, that any one proposes to legislate against water ballast tanks; but from what has recently been said against them, even such a proposal would not astonish us. A few weeks ago, a letter appeared in the Times on the subject, in which we are told of serious dangers due to the fact that "the upward pressure of the air in the water ballast compartment acts with increasing force the more the vessel is inclined from the upright."

The truth is, that dangers such as they, due to the empty ballast tank, so far from being caused by the air in it, would be slightly increased if there were no air at all, that is, if it were absolutely empty. After all that has been written upon the subject of the stability of ships during the last dozen years, in the way of popularising long known scientific truths, it is somewhat discouraging to find men, who evidently have some practical acquaintance with nautical subjects, falling into such absurd errors as to the effect of air in the double bottom. Other things being the same, the empty water ballast tank diminishes the stability of a ship simply because the cargo is higher than it would be if it were placed upon ceiling laid upon the ordinary floors of the ship. This effect, however, is a matter of easy calculation, and in well-planned ships it is taken into account in the general design. Every steamer should be so designed that when at her load displacement, with the ballast tanks empty and the holds filled, or nearly filled, with a cargo of medium density, such as coals or corn, there should be a fair margin of stability. Stability, so far as it depends upon form, is increased by increased beam, decreased by increased depth or greater fulness below water, so that if the design of a ship at first intended to have no tank, is to be altered to give her one, she should either have greater beam given to her, or her ends below water should be made finer. Till recently it was pretty generally believed that increase of beam necessitated increased power of propulsion, it was even affirmed in some quarters that a long parallel midship body might be put into a ship, without providing more than a trifling increase of steam power for its propulsion. The researches of the late Mr. Froude, however, have conclusively shown that, preserving the same displacement, the ship's breadth may often be advantageously increased, greater speed being obtained with a large breadth and fine. lines than with a smaller breadth and fuller lines. It has also been said that Lloyd's rules discourage increase of beam, and encourage increase of depth, and Lloyd's rules have often been blamed when the naval architect was really at fault. It may be readily admitted that Lloyd's rules for the scantlings of iron ships are not in any sense scientific, that they do not provide strength in a ship in any

way proportioned to the strains to which she is liable; they are not, however, open to this particular objection of encouraging deep ships. Lloyd's rules for scantlings depend mainly upon two quantities : the length, and the measure round of the half midship section. Other things being the same, greater longitudinal strength is obtained for greater depth, but the consideration that the ship may be subject to longitudinal strains when inclined at an angle, leads to the conclusion that a limit to advantageous increase of depth would be reached when it was equal to the breadth. Lloyd's rules, however, require that the thickness of iron shall be the same whatever the form of the midship section, whether that form be one of natural strength or not, the only measure taken by them being the periphery of the half midship section. It is true that when the length is so great, in comparison with the other dimensions, that the vessel comes under the rules for "extreme proportions," extra strength is very properly determined by the ratio of length to depth; and this may have given some colour to the charge against the rules, that they encourage depth. On the whole, it cannot be said that Lloyd's rules encourage deep ships. We do not for that reason commend the rules, because we think the one principle upon which rules for scantlings of ships should be based, is the provision of strength to meet probable demands upon it. If the committee of the Registry find that ships are being built of such form that, under ordinary conditions of stowage, they are unseaworthy, could they not deal with the question of stability by itself, and refuse a class to any ship which, when loaded, say with coal, was deficient in stability?

There is, however, one most unsatisfactory feature in many ships of recent design, referred to in an able communication,* which we published last month. We refer to the great height of the port-sills above the deck; in some cases we have noticed it to be from fifteen to eighteen inches. This is occasioned by the sheer strake being unnecessarily high, no doubt very much improving the look of the ship, and increasing the apparent freeboard, but really introducing an element of danger, which, in some

Nautical Magazine, January, 1880, p. 38.

cases, may be very serious. Ships of the type to which we refer have very high coamings—often more than three feet and thus there is little fear of the hatches being smashed in; but if the ship takes in a sea, and is not able to free herself from it at all for a height of fifteen inches, and only very slowly for a greater height, it is not to be wondered at that serious consequences may follow, when perhaps she has but a small margin of stability. Besides being too high to do their work properly, the wash-ports are frequently too small, or, if of a good area, they are unnecessarily high, and not of sufficient length, and thus their full area is only available when the water is very high on the deck. Vessels of the type to which we refer have often large deck erections-a topgallant forecastle, a bridgehouse, and a poop; these all help to increase the apparent freeboard, but the real freeboard of the ship is the height of the lowest part of her upper deck from the water, and that is often, we fear, so low that, if the cargo shifts a little, the vessel gets in a dangerous condition. While on this point we feel it necessary to refer to what one often hears on the subject of overloading in connection with a vessel's register tonnage, especially in reference to grain and coal cargoes. As we have often pointed out in this Magazine, a sailing vessel's register tonnage does furnish a material for an approximation of her safe load; but, in this respect, a steamer's register tonnage is altogether useless. Under the present law for calculating register tonnage, two steamers of, say, 2,000 tons each may be built from the same lines, be exactly alike in every particular both of hull and machinery, and yet if one of them has a small donkey boiler in a recess in the main boiler space, this trifle alone may cause a difference of 190 tons in the register tonnage. One steamer may carry cargo to the extent of twice her register tonnage and be overladen; another might be designed to carry three times her register tonnage and yet be perfectly safe. Nor is the gross tonnage of a steamer of much more use in estimating her safe load, unless we have full particulars of the weights of her engines and boilers and coals; these added to the weight of cargo would give her gross load, which is the only useful quantity to compare with her under deck register tonnage.

H