Having thus fully described the self-righting Life-boat of the Institution, we will consider the question as to the most advantageous mode of propelling Life-boats by manual labour ; for although sails must be employed for the performance of services at very long distances, and in a few localities, where boats are stationed in harbours, steam-vessels may be available to tow them ; yet as at nine stations out of every ten Life-boats have to be launched from an open, exposed, and generally flat beach through a heavy surf, and have to proceed entirely through broken water, the manual labour of their crews is the only possible mode of propelling them.
The question has often been asked – why are not Life-boats propelled by steam power? It is a very natural question when we consider the difficulty of rowing any boat against a strong wind, and the much greater difficulty of doing so when, in addition, the opposing force of a heavy breaking sea, such as Life-boats alone could face, has likewise to be encountered. The question is also now the more frequently asked, since steam-power has been employed usefully in boats of much smaller size than the ordinary coast Life-boats.
It is true that the failures of our present Life-boats to reach wrecked vessels are very few compared with their numberless successes ; but even these few form a sufficient cause for serious consideration of the question, as to the probability or possibility of making steam available for Life-boat propulsion. We propose, therefore, to briefly state the difficulties that have hitherto stood, and still stand, in the way of its application.
If force alone were required there could, indeed, be no hesitation in exclusively adopting it, for so enormous is the power of steam, that the strength of man, or even of the most powerful animals, is insignificant when compared with it. Moreover; if available, Steam would possess another and special advantage, in that it would do its work at comparatively small risk of human life ; whereas from ten to twenty men are required to work an ordinary Life-boat, often at the peril of their lives, steam Life-boats would be readily managed by four or five men.
Yet notwithstanding these great advantages, we fear that the difficulties in the way of propelling our coast Life-boats by the aid of steam are insurmountable. The only mode in which it can be made available is through the medium of ordinary steam-tugs, at the very few localities, such as Liverpool and Ramsgate, where there are out-lying banks and sheltered ports, from which Life-boats can be taken in tow at all times of tide, and be placed in any position to windward or leeward of a wreck which may be most convenient and safest for reaching it.
We will at once assume that screw propellers, with the requisite machinery for working them, can be readily fitted to Life-boats, and that by such means a greater speed might be obtained against a strong wind and a moderate sea; but the difficulties only then commence.
In the first place, a Life-boat, like the “stormy petrel,” which is rarely seen when the heavens are calm and the sea smooth, has its work to do amidst broken seas, and curling surfs where no other boats can live. Except in cases of collision and foundering at sea, when the Life-boat’s help can rarely be obtained, vessels are wrecked through running aground, either on outlying banks or rocks, or on the open coast; in both such cases, in nine instances out of ten, Life-boats have to be launched from an open and exposed beach through a high surf. On such occasions, if the shore be flat, they have to be conveyed through the heavy surfs which frequently in gales of wind form one continuous mass of broken water to the distance of a mile or more from the shore. On their course, heavy seas break over them, often filling them to the level of the thwarts, from three to four tons of water frequently breaking into a Life-boat from a single wave.
It will thus be readily conceived, even by those who have never seen a Life-boat, that there would be extreme difficulty in sufficiently protecting the fires of steam Life-boats from being instantly extinguished ; whilst at the same time preserving the necessary draught of air to enable them to burn, and sufficient access to them by the engineer in charge.
Let us imagine for one moment a steam Life boat submitted to such a test as beating for three hours over a sand-bank like the Goodwin Sands, with the sea continually breaking over her during the whole time, as will be described in a subsequent chapter. Even if the fires were not put out by the volumes of water breaking into and over the boat, is it likely that the machinery would bear uninjured such a series of great shocks from contact with the ground, and remain in working order?
The second difficulty arises from the extremely violent motion to which such boats are often subjected, as they are sometimes thrown into almost a vertical position, when bow or stern to the sea, one end being lifted high into the air, and the other buried beneath the water’s surface ; whilst the lateral motion is even more violent when broadside to the waves, the men on the lee side of the boat sometimes being up to their waists in the water. Many instances have also occurred of Life-boats having been altogether upset under such circumstances.
What would happen to the steam and fires of a Steam Life-boat, if upset, although, like the self-righting Life-boats of the Institution, she might remain only momentarily keel-up, we will not pretend to say, since no steam-boat of any description has ever yet passed through such an ordeal. We believe, however, that there would be the greatest risk of derangement of the machinery, and consequent disabling of a Life-boat, from the mere extent and violence of the motion to which it must frequently be submitted ; and it is scarcely necessary to add, that unless such a boat were likewise provided with a full crew and full complement of oars, with room to use them advantageously, her being disabled might, under some circumstances, lead to the destruction of herself and crew.
It has also to be remembered that the average draught of water of all Life-boats, except the heavily water-ballasted boats on a portion of the Norfolk and Suffolk Coasts, is only about nineteen inches ; So that the screw-propellers would need to be of very small diameter, and would be frequently above the surface of the water altogether, and thus work at a great disadvantage when going against a heavy head-surf.
A third, and, as far as we see, insurmountable difficulty, is the fact that the only class of men that are available to work the Life-boats on the coast, viz., the fishermen and other boatmen, would be incompetent to manage a steam-engine, and to keep it in proper order. They are skilful in the use of the sail and the oar, through having them in every-day use in following their avocations ; but they know nothing of steam or steam-engines, and as at the majority of stations the Life-boats would not be sufficiently often in use for them to acquire the necessary knowledge by experience, the National Life-boat Institution would have to seek competent trained men elsewhere. This might appear to persons unacquainted with the system of the Institution a difficulty easily to be overcome ; but it is not so, since, apart from the probability that the local boatmen would not, at many places, volunteer to work such boats, it would be necessary to maintain at each place an experienced engineer, and to pay him a sufficient salary for his maintenance ; for, unless he were to take the place of the village blacksmith, he would find no other employment in his own line of business.
The question then arises, can manual labour be applied in any more advantageous manner than by the use of oars? In considering this question, we must, at the outset, remember that there are only two principles of propulsion applicable to vessels floating on the water’s surface, viz., that obtained by the external pressure on the vessel by the wind, and that affected by a blow or pressure on the water exerted from the vessel itself, as by the paddle, the screw, the turbine wheel, and the oar, unless we include tracking or towing a vessel through a canal, or along the bank of a river, by men or by horses.
To proceed from the land to sea, we have then only the choice of the two first-named principles. In all the modes of applying the latter of the two, whether by the paddle, screw, turbine wheel, or oar, or by any other that can be devised, the water is used as a ful- crum, and the mechanical law of action and reaction is the source of motion, the reactionary force from the blow or pressure giving, what is in reality a back- ward motion to the vessel, just as the rebound of a ball from a wall or other plane surface is a backward motion caused by a force imparted to it in an opposite direction.
In exerting that force of any given amount such as the strength of ten powerful men, all we can do is to enable them to apply it in the most efficient manner, and with as small an amount of loss from friction as possible. Although one of the most ancient, if not the most ancient, instrument of hand propulsion, an oar is still the simplest and the most effectual, and we doubt if it will ever be superseded.
Life-boats have been designed with a cover or roof over them, the boats being propelled by paddles worked by hand-power. Even if it could be shown that such a boat was safer than an open one, we think it very questionable if the men who work them would consent to be shut up under cover, with no opportunity of seeing and judging for themselves of their whereabouts, and of the extent of any danger that they might be called on to encounter. Just as most persons are, naturally, more apprehensive of danger in the dark, when it may be invisible, although close at hand ; so, when their boat was thrown nearly perpendicular by a heavy broken wave throwing up the bow or stern, or nearly rolled over by a broadside surf, a Life-boat’s crew might imagine that the next moment they might be dashed to pieces on a rock, or that they might be hopelessly drifting into a fatal position from which they could never extricate themselves. There would probably also be often great difficulty in getting a wrecked crew safely on board, through a small open hatch in the roof-deck of the boat.
We have dwelt thus far on the peculiarity of roof- covering, since it is a general accompaniment of plans for propelling Life-boats by paddles or screws. Taking all these facts into consideration, we think it will be sufficient to enumerate the special advantages of an oar, to show that any other hand-propeller entering the list to contend with it will meet with a very formidable competitor.
The peculiar advantages of oars are as follows :
1st. They are constantly in the hands of our coast boatmen as well as of the crews of ships ; and their management is therefore not only thoroughly and prac- tically understood, but every muscle of the body which has to be brought into play is strengthened by its daily use, which advantages are undoubtedly of the very highest importance.
2nd. The friction in working them is very slight when they are properly fitted.
3rd. In the hands of practised rowers they can be accommodated to the motion of the sea, so that they can always be used at full power.
4th. If broken, they can be readily replaced, spare ones being kept on board.
5th. From their oblique stroke, on first immersion, the oars towards the bow and stern can be used with much effect in keeping a boat’s head up to the sea, and in turning her round, when required, in a short space. This also is a most important advantage.
On the other hand, their disadvantages are :
1st. That the force which has to be used to make the back stroke, and place the oar again in position, is a direct loss, allied with which is the loss of momentum consequent on the motion being backwards and forwards instead of being continuous.
2nd. When out of the water they must hold more o1 less wind, which is a disadvantage when rowing against a fresh gale.
II. “Rotary Propellers.”
Their chief if not only advantage would be, that the motion being continuous the whole of the force exerted is in one direction, round an axis, and that by the aid of a weighted or fly-wheel they may be made to retain their momentum, which would assist to carry them over any momentary extra resistance as, for instance, that of the blow of a heavy sea, and over those parts of their circuit when the men working them could not employ their strength to advantage.
Their disadvantages are:
1st. That the men who would be alone available to manage them would be un- accustomed to the work of turning the handle of a winch, and would not use their strength so advantageously a.s in rowing with an oar ; whilst, if they exerted themselves continuously, round the whole circle, the labour would be very exhausting, and they would soon succumb from fatigue, especially as they would be working in a con- fined atmosphere and in a covered boat.
2nd. They would be powerless to keep a boat’s head up to the sea when both wind and sea were very high, and on one bow.
3rd. The friction in working them would probably be greater than that of an oar.
4th. If the shaft of the screw or any other part of the machinery should get broken or out of order the boat would lie at the mercy of the wind and waves.
5th. In the case of paddles they would work at great disadvantage, consequent on the violent motion of the boat from side to side ; since the- paddle on one side would often be spinning round in the air, whilst the other would be too deeply immersed. A screw would likewise be frequently out of the water, from the pitching or longitudinal motion of the boat.
As these several propositions are almost self-evident, it is unnecessary to dwell on them at further length.