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inside of a week as to the coming of the south-west monsoon. And in all cases when we pass beyond these surface winds into the upper currents we find these currents are fast, an estimate of their speed being deducible from the general law that the velocity of currents increases from the lowest to the highest clouds at the rate of about three miles an hour for each thousand feet of height.

Probably there is no unexplored tract of the earth better adapted for an initial trial, or more likely to yield interesting results to an aerial traveller, than the heart of the great Arabian Peninsula. The prospects of discovering productive regions hitherto unknown by such a survey will be discussed in due place, while the comparative certainty with which the proposed transit of the country could be effected can need little insisting on. The writer has learnt from veteran officers of the P. and 0. service that from west to east across Arabia, as far as indications go, there is every probability of finding a favouring wind, and one persistently blowing overhead, if the right time of year be chosen. Moreover, Mr. D. G. Hogarth, whom, as a recent and reliable authority, I shall have to quote farther, states, from copious information, that the tract from the desert of Sinai to the centre of the Arabian peninsula ‘is swept by an eternally westerly wind, which keeps the Libyan sands ever moving towards the Nefud.'

This is encouraging information, and if we may assume that a choice of starting ground anywhere along the length of the Red Sea, and as far as Aden, is at the option of the aeronaut, then the journey, with only a moderately fast wind, does not appear very formidable.

A few principal routes work out somewhat thus. Starting from Aden, the Persian Gulf could be reached by balloon in nine hundred miles. From a point a little below Mecca the breadth of the country could be crossed with a W.S.W. wind in seven hundred miles, as equally from a point above Mecca, while from the first of these places, with a due west wind, the coast could be reached in about a thousand miles, and from the latter in eight hundred miles. With a north or south wind an important section of the peninsula could be traversed in five hundred miles, while from Mascat a yet shorter but serviceable voyage might be carried out.

It will be seen that the Persian Gulf offers peculiar facilities for the rescue of the balloon at the termination of its voyage ; and the nature and conditions of the task before the balloonist are the reverse of discouraging, as an impartial consideration will show; his special mode of travel, as compared with others, having distinct and allimportant advantages.

When a vessel is frozen in, her limit is already reached ; when the last camel is down, the traveller must take his final and hopeless survey ; but the resources belonging to the balloonist are more elastic and more reliable. If the wind before which he drifts is inadequate or contrary, it is within his power to seek other altitudes, with the strong probability of meeting with other currents ; while the prolongation of his travel is simply a question of initial cost and cubic capacity. When Count de la Vaulx landed in Poland he had still a large quantity of ballast remaining, and it was a debated point with him whether he should not add to his splendid achievement that of the further crossing of a desolate Russian steppe.

Coming now to the consideration of practical results which might be hoped for, and at the same time of the utter hopelessness of obtaining such results by any other means under political and physical difficulties at present existing, I may quote some recent and very valuable notes which have been generously supplied me by an accomplished engineer and traveller whose knowledge and experience can be second to none.

Colonel A. T. Fraser, C.E., in a paper read before the Society of Arts in 1895, advocated the construction of a railway across Arabia at the 30th Parallel, and a few years later went to Akabah to determine where such a railway should cross the valley previous to entering Arabia, which he considered the chief engineering difficulty. It may be seen from any good map that this proposed line practically marks the easiest possible route across the country, as also that where climatic conditions, as judged by the evidences of habitability, would be least severe.

Colonel Fraser, then, learning that Egyptian authorities could not get him Turkish permission, proceeded to Jerusalem, whence he was allowed to go to Maan and the 30th Parallel, the Turks, however, declaring they could not let him go more than one march south of that, or into the Akabah Pass, on any consideration. It ended in their granting him the run of Mount Hor for the sake of making observations, and Colonel Fraser, taking a small camp, remained two nights ; but the Bedouins saw his lights, and there were signs that it would have been unsafe to stay longer.

Any consideration of the projected Bagdad Railway would, it is unnecessary to say, be outside the present discussion. In the opinion of the secretary of the Ottoman Railway Company the enterprise would not pay for carriage grease ; and, whether this be so or no, it suffices to say that Bagdad approaches the 34th Parallel, while the district which would be opened up is already sufficiently well known and not calculated to repay development.

As to the feasibility of effecting a balloon inflation at a more southerly latitude, which should preferably be on the shore of the Red Sea, and which should lead to a sky passage across a tract of the peninsula of perhaps the greatest economic value, Colonel Fraser insists that an ascent from the east of the Red Sea would not be easy, as it is the sacred province of the Medjar, confirming this opinion by the fact that he himself could not so much as unroll a map of his route in a Euphrates valley if there were any Turks about.

hut the Bedou to stay longer: paodad Rail

To meet this difficulty, it may be pointed out that it would not add more than a few miles to the voyage if the inflation were effected on the west bank of the Red Sea ; and possibly it might even be carried out with no great difficulty, and with perfect immunity from trouble, from one of the many islands in the lower latitudes of that sea.

Lastly, there is conceivably the expedient now being developed of a self-contained hot-air balloon, for the success of which the air lying over Southern Arabia would be specially favourable.

It remains to give due attention to such meagre information regarding Central Arabia as we at present possess, and to consider the knowledge we might hope to gain by balloon exploration, and here we would first examine a map prepared from facts supplied by Mr. Hogarth and others; and, by way of sample of the country, let us note that a central patch, marking what we may regard as the heart of the northern half of the country, and standing, roughly speaking, between the parallels of 27o and 29°, is claimed to be partially known. Let us, however, further estimate what this really means. I take it that no more experienced or adventurous explorer ever penetrated into the Arabian interior than Mr. Wilfrid S. Blunt, whose route and survey, drawn by his own hand, has been published by the Royal Geographical Society. To use his own words, he finds this portion of Central Arabia occupying its old condition of an almost fabulous land, whose real nature is still a matter of doubt if not of curiosity. For more than two hundred miles from Kaf to Jof there is no inhabited place, while it is only along the course of the Wady that there are wells which attract the Bedouins. Jof itself has some five hundred houses and palm gardens, and in its whole oasis there may be seven thousand souls. Thence, with a splendid equipment of camels, it cost the experienced traveller eleven days to cross the Nefud-a true and typical desert, and yet so far from unproductive that its mere red sand after rain becomes actually covered—so Mr. Blunt believeswith grass and flowers. More than this, it is, we learn, in one way blest above all other places—'fleas do not exist there. Of that land Sir H. Rawlinson has said that it is the most romantic in the world, with a sort of weird mystery about it from the very difficulty of penetrating it. Mr. Hogarth adds his own testimony as to this approach to Arabia, asserting that it is only entered with great difficulty and pain by man and beast, so that present-day pilgrims have almost abandoned the land route for the sea ; and the central plateau is become more an island than ever. If, now, we pass to examine the rich and, from its neighbourhood to the seaboard, the more accessible oasis of Hasa, the land of running streams and many springs, we find it is but a mere narrow strip, while immediately without to south and west stretches the unknown.' Further yet, when we turn to the nearer and more luxuriant spots of the south-west corner of the peninsula, the portal, as it were, of the region we seek to reach, the alluring plains which ere now have led explorers to hope to gain a footing, whence they might extend our knowledge—the ‘Happy Arabia’ of ancient geographers—where once the waters were held back by huge artificial dams, we find ourselves equally baulked, for we learn that the newest of these works is no later than the sixth century. All are broken now, and the waters filter, away, allowing the sand to creep once more about the villages.

Enough. We can but avail ourselves of such legendary information as is to hand to at least form some allowable conjecture of what the great unknown has to reveal, and how well worth at least a cursory survey. It appears that from whatever side this region is approached, tribesmen dwelling on the outskirts have, in place of any definite information, mere tales of awe and wonder bred of a certain superstitious terror. It is a wilderness upon which Nature vents her fiercer moods ; it is a land of wrath where the earth is shaken and the soil in perpetual unrest. There is a vague talk of saline oases and of wild palm groves ; but it is said that ere men can reach these the earth opens to engulf them, or they are swallowed up in subtly shifting quicksands. The mysteriousness of these reports endows the country with a species of enchantment, and we can no longer regard the so-called desert as a mere waste—the more so when we unmistakably trace up to the limit of where any European has yet trodden how beneficently Nature has dealt with the land, converting the desert soil into very gardens of Paradise, and whole regions into luxuriant fertility. Every thoughtful traveller through the Red Sea must look out over those blue mountains to the eastward, and feel that beyond those far and fascinating slopes must lie the hope of new discovery and fresh scope for enterprise.

Now, if the generally accepted estimate of the upper wind currents is fairly correct, then, for a preliminary aerial survey, a balloon no larger than that recently employed by Count de la Vaulx might suffice, especially if the mode of inflation by hydrogen, artificially produced on the field, were adopted, and for the rest little more would be needed than a proper outlook maintained on the eastern shore of the peninsula. This, of course, is essential, as at the end of the voyage the aeronaut will need certain efficient assistance. If he elect to alight on the coast, he will not succeed in doing so without assuredly having been sighted by the fanatical native, who, to say the least, is liable to give trouble. If, on the other hand, he prefer to drop on the water, as many a balloonist has with safety done ere now, then there must be those afloat and sufficiently near at hand who, having been watching the balloon in the sky, will have opportunity to direct their course and stand by.

An initial experiment, altogether inexpensive, comparatively speaking, and readily carried out, should be made by fleets of pilot balloons designed to remain aloft in such a climate as the Arabian desert for the time considered sufficient to cross the breadth of the country, dismissed from chosen positions on the west side, and looked out for on all the available places on the eastern seaboard. It would not be necessary that these should be captured. If batches were dismissed from different points on different pre-arranged dates, and if after crossing the land any were sighted in the sky, the route that they had taken, as also the time of transit, would be well determined.

But so far we have not said all that is to be advanced as to the chances on the side of the aeronaut. Should it appear from preliminary tests that the passage across the peninsula would occupy a longer-even a far longer-period than we have assumed, the resources of the aeronaut may yet by special means be rendered fully equal to meet any enforced detention in the sky. Ordinary aerial voyages, though they seldom fail through any inanition of the balloon itself, are nevertheless commonly undertaken without any special economising of the gas which, for safety against bursting as also for the sake of a certain indolent convenience, is allowed to escape by natural diffusion from the neck of the balloon, kept constantly open. A suitably devised valve, however, might be made to considerably diminish this waste of gas at the lower aperture; while from the upper opening, usually closed with a hinged valve, the ordinary and by no means negligible amount of leakage can be entirely obviated by a solid valve of varnished silk, which is firmly bound over the aperture, and which remains perfectly impervious until finally rent open at the termination of the voyage. But should it be considered that, even so, a single balloon would not possess sufficient 'life' for due safety, then a method that has been advocated by practical aeronauts, but never yet needed to be put in force, could be adopted. This consists in starting on the voyage, not with a single balloon, but with two or more in tandem, and so arranged that when by lapse of time the main balloon became unduly shrunken it might be replenished by the gas from a spare balloon, which could then be discarded.

Anyhow, the fact remains that seventy years ago a balloon of no extraordinary size, and with no special fittings, inflated, moreover, only by household gas, then but recently adopted for ballooning purposes, carried three passengers and an enormous reserve of ballast across five hundred miles in eighteen hours. This voyage, conducted by Charles Green, extended from London to the heart of the German Forests, and was continued, moreover, through a long, cold winter night, which must have told considerably against its sustentation, yet at its termination, dictated only by considerations of convenience, so much ballast was still remaining that there can be no reasonable doubt that with the sun about to rise the length of the journey might have been doubled if desired. It may further be pointed out that no balloon voyage soever yet undertaken in Europe or America has been carried through under conditions which would tend most to its

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