The boat was made by Messrs. Edgington from a model which we had previously constructed and tested as to its buoyancy and sailing qualities. The framework was of ash battens, 3in. wide and ¾in. thick. The uprights at stem and stern were mortised into the keel, as well as into the corresponding fore-and-aft batten above; they were secured by cross lashings passing through holes properly bored for the purpose. The gunwales were lashed on; and then the thwart pieces, 6in. wide, were secured in the same manner. The four canvas bags, each cut so as to form half a whale boat, 15ft. long and 18in. in the half breadth, were then laced in and inflated. Each rowlock was formed of two pieces of ash screwed to the gunwale, as seen in the preceding engraving; and two oars and a lug sail completed the equipment. The whole might be used either as a double canoe or as two separate boats, and Mr. Gregory was much pleased with them when put together; but, in consequence of a technical difficulty at home, they were not so efficient as they ought to have been. We had agreed with Messrs. Edgington as to the quality of canvas and of the sewing to be used in every part, but on applying to the Waterproofing Company he found they would not waterproof his work, nor allow him to do it. He had therefore to give over the whole of the work to the company. When finished, we found that the seams were not stitched at all, but cemented together; and, though warranted to stand 170° of heat, we found that with the strain of actual use upon them they softened and gave way. If the sections in their proper form were made of stout canvas, with the india-rubber bags, so large that they should bear no strain, inclosed within them, this would be a serviceable boat—for the india-rubber did not actually melt with the heat, but just softened, so that it was unable to resist the strain upon it. We had taken them up the river, about thirty miles, in the schooner’s gig, to fill with fresh water, and instead of standing a heat of 170° they burst at 120°.
Although, as we have stated, our double inflatable boat partially failed in Australia, from the inability of the waterproof cement to bear the intense heat to which it was subjected, we believe that, had Messrs. Edgington been allowed to waterproof their own work, or had the company consented to waterproof the sections, properly seamed by practical tentmakers, according to the directions we gave, the finished boat would have been as successful in every respect as was the model.
When required for an exploring trip up the river, we decided to use them not as a double boat, but as two single ones, and we spent some days in securely stitching round every seam that should have been so treated by the original maker. Every one will understand how the fibre of the waterproof cloth would no longer close up round the threads, as would that of the new canvas, so that, notwithstanding all our care, there was always a little air leakage; however, spare bellows had been provided, and one was apportioned to each boat.
Four or five 6lb. tins of preserved beef were thrust in between the sections in each boat, so as to rest along the keel, our lighter stores were laid as might be said “on deck,” and with two small oars in each we started, pulling up wherever there was sufficient water, and when we came to the dry intervals, slinging the boats one at a time under two oars, and carrying them easily with all their cargo to the next water. The voyage lasted some days, and the boats, therefore, occasionally required re-inflating.
Canoe for one man.
If the traveller only wishes for the means of ferrying himself over rivers, he might take a couple of waterproof tubes, not less than 7ft. long and 8in. in diameter, inclosed in unprepared covers of canvas so tight as to relieve them from any strain, and connected by one breadth of canvas for him to sit upon. A small frame should keep these parallel to each other, and about 20in. or 2ft. apart; and the frame should be kept just above the water, so as not to impede the motion. It is a great thing to be independent of native help. If a man has his own canoe, however small, the people will come to offer theirs; but if he has none, they will make a hard bargain with him.
Metal boats.
Perhaps as good a material as any for a boat, if the explorer is able to carry it, is pure sheet copper, of about 1lb. to the square foot. It is flexible, easily worked, will turn and bend in any form and at any angle; it may be folded down to a sharp edge like a sheet of paper, and opened again, a test which no iron ordinarily procurable could stand; it is nearly indestructible, and retains a proportionate value as old copper however much it may be worn.
We have heard of an officer who had the two ends of a yawl or whale-boat built of copper, and, though the stem would frequently be doubled up by touching the ground in crossing the bar of some African river, no leakage took place, and half an hour’s skilful hammering brought it into shape again. We believe that the boats, or at least one of them, on the expedition of Mr. Lynch to the Dead Sea and the Jordan, were of copper. If we remember rightly a copper boat was carried in sections upon camels to Lake Chad.
Captain Burton took to Zanzibar a boat of corrugated iron, which was so speedy that the Arabs called her the Runner-away; it would be interesting to know the details of her construction. We at one time experimented with galvanised iron, but did not find it sufficiently flexible to bend so sharply as we required. In consequence of this—when preparing, in conjunction with a long-known friend, Mr. James Chapman, for a journey across Africa, from Walvisch Bay, on the west coast, to the Victoria Falls, from which we hoped to navigate the Zambesi to the Eastern Sea—we decided on building one of copper; and many reasons induced us to make this on the principle of a double canoe or twin steamer: in the first place, it would be difficult to carry a boat of more than three feet in breadth or depth, in an ox waggon, and these dimensions would afford room only for the closest possible stowage of our own persons, and a very scanty equipment. It was also, probable, that the boats would have, at rapids like Chicova or Kebrabasi, to be taken out of the water and carried over rugged and intricate country, where their length would render it impossible to manage them.