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We may here notice an incidental discovery, of very recent date, and of great importance to canal navigation. Desirable as it was to obtain speed, it was soon found that steam was inapplicable for that purpose on canals, as the paddle-wheels, however fitted to work above or below the surface, raised a wave which destroyed the banks: the same injurious effect, though in a less degree, took place if the speed of the tracking-horse was accelerated to five miles an hour; the pace is therefore usually kept down to four miles, or under, and even then a wave accumulates at the bow of the vessel, to the height of from one to two feet, and the resistance thereby occasioned is found to distress the horses in their endeavours to overcome it. The undulation occasioned by this wave is stated to be perceptible at a mile's distance a-head of a slow-going coal barge. A gentleman of the name of Houstoun, neither theorist nor engineer, discovered, by mere accident, a complete remedy, not only for this obstruction to the speed of the canal-boats, but against the injury done to the banks. He happened to whip his horse, attached to a gig-built boat on the Paisley canal, to a speed of eight or teu miles an hour, at first starting, and observed that the animal was able to sustain that speed without difficulty; that the water continued smooth; that no wave rose up at the bow no ripple on the banks.
This experiment, contrary as it was to the theory of the resistance which bodies floating in fluids meet with, and which every engineer believed to be in the ratio of the square of the velocity, was not lost on the proprietors of the Paisley canal. Their long and narrow boats, with spoon-shaped bottoms, and light draught of water, capable each of carrying a hundred passengers, with their baggage and other small parcels, have for the last two years passed several times a day between Glasgow and Paisley, a disiance of twelve miles, in one hour and a quarter, with ease to the horses, the passengers paying a fare at the rate of three farthings a mile, just half the rate of travelling in the Liverpool rail-road coaches. The proprietors of English canals have at length, somewhat tardily, taken it up, and we understand it either is, or will fairly entitled; they have the modesty to stretch their pretensions even to the invention of the steam-boat. Their Fulton, of whom they so much boast, received his notions on the subject from Lord Stanhope in England, and Miller and Symington in Scotland. The merit, however, of the discovery is due to none of them, but to an humble individual of the name of Jonathan Hulls. The late Mr. John Rennie said — Don't talk of Fulton, or Miller of Dalswinton, or Lord Stanhope, as the inventors of the steam-vessel : Jonathan Hulls, and he only, was the inventor. Look at the print in his little book, published in 1737, entitled “ Description and Draught of a new-invented Machine for carrying Vessels or Ships out of or into any Harbour, Port, or River, against Wind and Tide, or in a Calm," and in it recognise at once the steam-boat, by its paddle-wheels, its smoking chimney, and the tow-rope from her stern, to the two-decker she is dragging.'
soon be, in full operation on the Grand Junction Canal, to the great dismay of the projectors of the London and Birmingham rail-road.
But to our present purpose-the communication with our Indian establishments by means of steam-navigation. It is a subject which, like many others hastily taken up, and without due investigation, is calculated to raise sanguine and unreasonable expectations, especially ainong those who are interested in its success, and who hope to reap the benefit without contributing to its expense. It appears indeed, from the newspapers, that a considerable clamour has been raised against the directors of the East India Company, the Board of Control, and the Admiralty, by certain merchants of London and Liverpool, for their tardiness or unwillingness to establish at once a regular steam-conveyance to and from our possessions in India. What the Admiralty has to do with it, we have yet to be informed; and this vituperation, under the present uncertain circumstances of the East India Company, is, at all events, premature.
But the truth is, that neither the India Board nor the Company have been unwilling or tardy to take into consideration, and to direct the necessary inquiries into, the practicability of establishing the communication in question : the latter have been in correspondence on the subject with the Indian authorities since the year 1829, and encouraged experiments in India, as appears from Mr. Prinsep's book, so far back as the year 1824. The estimates, however, which they have received from India, of the expense required for opening and keeping up a communication of this kind, are alarming
• We are not insensible,' they say in a letter to the Governor at Bombay, “to the advantages of a rapid communication with India, and of the importance of encouraging the application of steam to that purpose.
We are also disposed to believe that a steam-communication the Red Sea-and still more, if it should be found practicable, by the Persian Gulf and the River Euphrates—would open the way to other improvements, and would ultimately redound to the benefit of this country, as well as of India, and if our finances were in a flourishing state, we might possibly feel it a duty to incur even the enormous outlay specified. But in the present condition of our resources, we cannot think the probable difference of time, in the mere transmission of letters, a sufficient justification of this. At the same time, we deem the subject too important to be lost sight of or hastily dismissed; we shall therefore not fail to carry on inquiries into the practicability of effecting the end in view, at a reasonable expense. We desire that you will also do so, &c.'
We too have directed our attention to this important subject, and hope to be able to give to the Directors some more correct information than they appear as yet to possess, with regard to the comparative facilities and expenses of the two routes they here allude to; and we shall begin with that by the Euphrates, as being the least known, and because we have now before us everything necessary for our purpose, detailed in the able and minute survey of that river by Captain Chesney, who, at a considerable hazard of life, persevered in accomplishing his object, and has happily returned home to communicate the result of his labours in a report.
Captain Chesney sets out by observing that the great river' of Scripture, linked as it is with the earliest times and the greatest events in the history of the world, and the ancient channel of extensive commercial intercourse, is not likely to disappoint any moderate expectations which may have been formed of its importance and utility.' In the upper part of ils course, it struggles in a tortuous channel through high hills, forcing its way over a pebbly or rocky bed, at the rate of two to four and a half miles an hour, according to the season of the year and the different localities, carrying with it a considerable body of water, but without any cataracts, though the stream meets with frequent obstructions (above and a little below Anna) by a rocky bottom, and is shallow enough in places to allow camels to pass in the autumn, the water then rising to their bellies, or about four feet and a half. This portion of the river is compared with the scenery on the Rhine below Schaffhausen ; its bank is covered thickly with high brushwood, interspersed with timber of moderate size.
It is here studded with a succession of long narrow islands, some of them thickly wooded, and others cultivated; and on several of these are moderate-sized towns or villages. The banks of the river are well peopled, not only with Bedouin Arabs in tents, of whom there are many thousands, but also with permanent residents in houses of brick, mud, stone, and reeds. The following passage carries us back to a remote antiquity, when a civilized society crowded the banks of the Euphrates.
*The scenery above Hit (in itself very picturesque) is greatly heightened, as one is carried along the current, by the frequent recurrence at very short intervals of ancient irrigating aqueducts, which, owing to the windings, appear in every variety of position, from the foreground to the distant part of the landscape; these beautiful specimens of art and durability are attributed by the Arabs to the times of the ignorant, meaning the Persians when fire-worshippers. They literally cover both banks, and prove that the borders of the Euphrates were once thickly inhabited by a people far advanced in the application of hydraulics. These speaking monuments have, as may be supposed, suffered in various degrees, and the greater portion are now in ruins; but some have been repaired, and kept
up for use, either to grind corn or to irrigate, having a modern wheel attached on the ancient, simple, and most efficient model; the whole being in some instances sufficiently well preserved to show clearly the original application of the machinery.
• The aqueducts are of stone, firmly cemented, narrowing to about two feet at top, placed at right angles to the current, and carried various distances towards the interior, from two hundred to twelve hundred yards; their height being regulated by the level of the spot to be irrigated: the shorter distances have one row of arches, and the longer ones tiro, one above the other, and both extremely pointedin fact, almost forming a triangle from the key-stone to the spring of the arch. At the one extremity of the structure, which is some little distance in the rirer, the building makes a turn parallel to the stream, and there widens sufficiently to contain one, two, three, occasionally four wheels, parallel to each other, and revolving with the current, each of about thirty-three feet diameter, and having a number of earthen vessels paced around the exterior rim, which, dipping a few inches into the water, are filled, and forced round by the current in succession, the open end foremost, until each in turn reaches the top, and there discharges its contents into a trough.'
These wheels differ little from those used in Persia, and are precisely the same in principle and construction as the bamboo wheels of China. Captain Chesney states that, just above each aqueduct, there is a parapet wall crossing the stream from side to side, leaving only an opening in the centre for boats to pass; the object of these subaqueous walls being to raise the water to a sufficient height at low seasons, so as to give it an impetus, and to afford an increased supply to the wheels : and that they are not, and never were intended to be means of defence, which Alexander mistook them for. Such stone-barriers existed also in the Tigris, in the time of the Macedonian conqueror; and it is not doubted that many, now visible in both rivers, rest on the bases of the ancient fabrics.
About ten miles below Hit, all these things disappear; the hills gradually diminish, and the surface becomes comparatively fat, A few trees are scattered along the banks, but there is little brushwood: the current becomes duller and deeper, with an appearance approaching that of the Danube between Widdin and Silistria ; but, in the captain's view, much more animated the banks being covered with Arab villages of mats or tents, almost touching each other ; with numerous flocks of goats, sheep, and some cattle, feeding near them; also beautiful mares, clothed and piqueted close to the tents, their masters strolling about, and the slaves busily employed in raising water by means of pullies.' This, too, is a common machine throughout the eastern world. Sometimes the water is raised from the river to the high bauks by bullocks traversing up and down an inclined plane. • They appear to have been known,' says Captain Chesney, and used, in Mesopotamia, from the earliest times; and the river's bank is quite covered with them, all at work, and producing all the fertility of Egypt, as far inwards as irrigation is extended; beyond which the country is, generally speaking, a desert.'
From Hit to Hilla or Babylon, little is seen but the black tents of the Bedouins; the land mostly desert, with the date-tree showing itself in occasional clusters : but, on approaching Babylon, cuts and canals, for the purposes of irrigation, became more frequent. Two streams, one above, the other below, the ruins of Babylon, take the common eastern name of Nile. For about thirty miles below Hilla, both banks are crowded with mud villages, embedded in date-trees; and to these may be added a multitude of huts, formed of and supported by bundles of reeds placed slanting, at four or six feet apart, and covered with matting of the same material ; villages of this kind are hereabouts exceedingly numerous, and generally built around a sort of mud fortress, with semicircular towers and battlements, inclosing a space sufficiently large to secure all the grain from depredation.
Lower down, towards Lemlun, the country being level, and the banks little raised above the river, irrigation is carried on by the simple operation of a lever, moveable on a pole, having a leather bucket at one extremity and a basket of stones at the other, being the same that is used in Egypt and Spain; and, we may add, in the garden-grounds beyond Hammersmith. The banks are here covered with cultivation, fringed with a double and nearly continuous belt of luxuriant date-trees, extending down to the Persian Gulf;' and attaining,' says Captain Chesney, ' a degree of perfection, with a variety of productiveness, far beyond those of the Nile.'
At Lemlun, the Euphrates throws off its branches, forming a delta, which is said by Captain Chesney to resemble that of Damietta; and here, when the river is swollen, the country is inundated, to the extent of sixty miles in width, covering the fertile rice-fields known by the name of the Lemlun Marshes. Here, as in Egypt, the huts of the peasantry are surrounded by water; and it is no uncommon occurrence to see a whole village afloat, and the people following on foot, or in their canoes, to arrest the materials of their dwellings, which are erected on the same spots, and exposed to the same disaster, the following year.
At tifty miles below Lemlun, the marshes terminate ; and here the river is greatly increased in depth and width, by a junction of a branch of the Tigris, called the Hie-taking a breadth of about