and Campania, the White Star Majestic and Teutonic, the P. and O. Himalaya, Australia, Victoria, and Arcadia, and the three Empresses of the Canadian Pacific Company. Eighteen other steamers are included in the second class, without subsidy.

The idea of armed mercantile cruisers originated with Mr. Ismay, of the White Star line. In 1885 he pointed out to the Government that in the event of the Suez Canal being closed, a vessel such as his firm proposed to build could land troops in India by way of the Cape almost within the same time that would be required to make the passage by the Canal. Mr. Ismay's proposal was accepted, and the Teutonic, the first of her class, was laid down. This vessel, typical of her successors, mounts twelve quick-firing Armstrong guns, eight on the upper and promenade decks, and two on each turtle-back. The Teutonic can reach Halifax in five days, and Cape Town in twelve and a half days: she can land troops at Bombay via Suez in fourteen days, at Calcutta in seventeen and a half days, at Hong Kong in twenty-one and a half days, and at Sydney in twenty-two days.

During the recent war between the United States and Spain, four cruisers belonging to the American line were requisitioned for service. These were the Paris, New York, St. Louis, and St. Paul. The first two, as already mentioned, were the famous Cities of Paris and New York, originally Inman steamers. These vessels were engaged as cruisers from April until September, during which time they suffered no mishap or breakdown, and the owners received the thanks of the President of the United States.

Though our own armed cruisers and the Royal Naval Reserve have not been put to a practical test, yet the best results may be confidently anticipated from these allies. The smartness of the officers, engineers, and seamen on the great liners is largely due to the influence of the few months' discipline to which they have been subjected in Her Majesty's Navy. The reserves include officers and seamen, engineers and firemen. The two latter have never been popular services, and the great companies offer more attractions to these men than the Royal Navy, the engineers of which always feel that they occupy a position subordinate to their real value as combatants. The modern battleship is simply a huge machine, and on the engineer and his staff will devolve the gravest responsibility in time of trial-an excellent reason why the modern liners, which are the highest embodiments of marine engineering, should be the nurseries of reserve men. There

are now about twenty-seven thousand trained men of all classes -officers, engineers, seamen, and stokers-ready to take their places in the navy should a naval war break out.

It must be recorded as one of the greatest triumphs of modern naval science, that huge steamships are built to satisfy the requirements laid down for armed cruisers without any sacrifice of the accommodation and comfort of passengers. The ordinary observer would note little difference between the appearance of the armed cruiser and the common type of mail steamer. The chief difference, besides the gun arrangements, is that in the former the engines, boilers, and rudder are placed wholly below the water-line, and are thus well protected. Ample capacity and great steaming-power are essentials in an armed cruiser. The Oceanic, which is a cruiser, has nearly 3000 tons greater capacity than any other vessel in existence, and over 5000 tons more than any vessel of her speed. It was with difficulty that the early steamers could carry enough coal to last the Atlantic voyage. The Oceanic can store enough to take her round the world at a speed of twelve knots.

May we now attempt to forecast the future? The nonprofessional reader is inclined to believe that, since the speed of ocean-steamers has regularly increased, and records have constantly been broken in the past, the same process may be indefinitely continued. The early Atlantic vessels made passages of from thirteen to sixteen days: the voyage is now done in five and a half to six days. Having been thus reduced by more than one-half in the course of sixty years, why should it be supposed that finality has been reached? This seems

sound reasoning. But sanguine persons who entertain the hope of a considerable future reduction in the speed of ocean transit do not, we venture to think, clearly realise the conditions, or the price which has to be paid for high speed.

Approximately, the power required to propel a vessel increases in the ratio of the cube of the speed. To double the speed, therefore, the power would have to be increased eight times. Any marked advance in this direction is evidently not to be anticipated in the present condition of marine engineering. Engineers admit the possibility of great advances through the application and improvement of the steam-turbine, but as yet these are only far-off dreams.

The torpedo-boat, which can travel half as fast again as a liner, is able to do so because everything is sacrificed to speed. The torpedo-boat is occupied almost wholly by machinery, and this is very light. The weight of its machinery will range from about thirty-five to seventy pounds for each indicated Vol. 191.-No. 381.

H

unit of horse-power which is developed by the engines. But the machinery of a liner will weigh from three to five hundredweights per indicated unit of horse-power. The first has neither cargo nor passengers to carry; the last is a commercial venture, depending on these for success. The magnitude of the venture may be estimated from the fact that a modern Atlantic liner must carry from 1000 to 1600 passengers and 2000 to 4000 tons of cargo, besides her 2000 to 3000 tons of coal, and must earn about 16,000l. clear per trip, before a penny of profit is made. At the same time, passengers demand more and more room. The Lucania, for example, is given up so much to passenger accommodation that only 1600 tons of cargo can be carried, with 2000 bags of mails.

Again, increased speed is accompanied by most unpleasant vibration. To avoid this, fast ships already have recourse to many expedients. For instance, the boiler-rooms of the Campania have double casings, the space enclosed being filled with a material which acts as a non-conductor of sound. A further increase of speed might easily render the vibration almost as intolerable as it is on a torpedo-boat.

Further, those who are sanguine respecting the probability of largely increased speeds fail to take account of the conditions which have facilitated the past increase in the rate of travelling. The reduction of speed by one half has occupied sixty years, which have been characterised by the most remarkable developments in the machinery of propulsion. Without such developments, these great advances in speed would not have been possible. There is good reason to believe that the sources of energy at present available, and the mechanical details of their transformation, have now and for several years past been utilised to the utmost degree. Therefore, unless some further radical improvements in the machinery of propulsion occur, no important increase of speed can be obtained. The truth lies in a nutshell: energy cannot be created, it can only be transformed. To produce a given speed, a corresponding amount of energy must be stored up and utilised in the vessel. Coal contains the latent force, while the machinery forms the agency of utilisation. To gain a little more speed would involve storing much more coal; and this would mean a demand on space so disproportionate that there would not be enough room left for passengers and cargo to render a vessel a paying venture. It would mean turning a liner into a sort of magnified torpedo-boat. Already the consumption of coal is enormous on a liner; it amounts to 350 or even 500 tons a day. And yet, though the aggregate is so large, the actual proportion of coal consumed to the energy or

horse-power developed is now so extremely small that it seems impossible to reduce it further. The best liners do not burn quite 1 lb. of coal per unit of horse-power developed per hour. The earlier steamers burnt 5 and 6 lb. per unit per hour; so that, though the energy necessary for propulsion at the present speeds is, say, eight times that developed in the early steamers, the coal required is only about one third or one fourth of what would have been required for an equivalent energy in earlier days. The Great Eastern failed, not because she was a big ship-for she was not so heavy as the latest liner— but by reason of the vast dead-weight of coal which she had to carry. At that period the marine engine was a weakling in comparison with its successor of the present day, and the boiler pressure was very low. The result was that the Great Eastern required more than three times as much coal as a modern liner requires, in order to produce a given degree of power. It is, therefore, we think, safe to predict that no important advance in the speeds of liners will be made by existing types of boilers and engines.

But though no great improvement may be in store, we may well be content with what we have. A wonderful advance in the art of building and equipping steamships has been made, and the story of this advance has an interest, an excitement of its own. Machinery, steam, and steel are not without their poetry. Romance has not disappeared from the seas with the white-winged clippers, nor will it disappear while the great steamships plough their courses, regardless of the trades, doldrums, and calms, of hurricanes and tempests, of icebergs and all the other perils of the sea. Safer and more comfortable than their predecessors, both for passengers and crew, they are one of the most marvellous mechanical products of the nineteenth century. They are the crown of ages of navigation, carrying our thoughts far back through thirty centuries to the youth of the world-to the daring mariners of Norway and Phoenicia, to the triremes of Carthage and of Athens, to the 'hollow ships' which were beached before Troy, and to the mythical heroes who sailed on the quest of the Golden Fleece.

ART. V.-1. The Wild Garden. By W. Robinson. edition. London: John Murray, 1894.

Fourth

2. Garden Craft, Old and New. By John D. Sedding. London: Kegan Paul, Trench, and Co., 1895.

3. Wood and Garden. By Gertrude Jekyll. London: Longmans, 1899.

THE

HE dictum, it is all a matter of taste,' has in it that soupçon of truth which may be found in many an accepted saying. It is true so far as it goes, but that is only a very little way. The canons of taste are the verdict of centuries of cultivated thought devoted to a given subject; and, though no one can be denied the right of private judgment, the balance of truth will generally incline towards the experts. Their opinions have already been sifted and over-ruled or modified; and to set aside their garnered wisdom is an enterprise not lightly to be undertaken.

Our love of flowers has a long pedigree, for though the gardens of the Romans were laid waste during the barbarism which followed their departure, the gardener's art was revived by the Church. War and rapine-with the necessity of protecting rather than embellishing the narrow precincts of a stronghold-were the employment of the laity. But within the peaceful walls of the monastery the gentler arts found a retreat; and the work of acclimatisation was carried on with zeal and intelligence. It was not until Tudor times that they could emerge into the world once more. It is to the stately decorum of those days that the school of art appeals. But if Bacon discourses rapturously of 'prince-like gardens,' Linnæus wept with delight at the first field of gorse which he saw in bloom. If the creation of a garden be an attempt to enhance the beauty of the world, there is room for all sorts of gardening; and if there be any spot from which the turmoil of controversy should be excluded, it is here. When Epicurus planted a garden, his design was not to provide an incentive to disputation, but a needful sedative.

How completely this principle may be overlooked is manifested by the first two of the books before us. Possibly it were unreasonable to expect an architect and a landscape gardener to see with the same eyes; yet there should be an intimate sympathy. The finished picture should lie before the mind's eye of the architect; but years before the first stone is laid, the trees and shrubs, which are to be the main features of the garden, should be started on their career. The quarrel might well have been avoided had each author known better how to