A Thousand Miles in the Rob Roy Canoe on Rivers and Lakes of Europe

by John MacGregor

The precise angle to the line of the course which the boat's longer axis ought to have will depend upon what is to be done next after passing between B and C, and hence the importance of being able to effect the passages in fig. 1 and fig. 2 with the axis at any required angle.

We may next suppose that one of the three rocks, say B, as in fig. 4, is a breaker which will deflect the current (as indicated by the dotted stream lines), and it will then be necessary to modify the angle of the boat's axis, though the boat's centre has to be kept in the same course as before.

It will be seen at once that if A were a breaker the angle would be influenced in another manner, and that if C were a breaker the angle at which the boat should emerge from the group of rocks would be influenced by the stream from C also; but it is only necessary to remind the reader that all the combinations and permutations of breakers and sunk rocks need not be separately discussed,—they may be met by the experience obtained in one case of each class of circumstances.

Fig. 5 represents a circular current over the group of three rocks. This is a very deceptive case, for it looks so easy that at first it is likely to be treated carelessly. If the boat were supposed to be a substance floating, but without weight, it would have its direction of motion instantly altered by that of the current. But the boat has weight, and as it has velocity (that of the current even if the boat is not urged also by the paddle so as to have "way" through the water), therefore it will have momentum, and the tendency will be to continue the motion in a straight line, instead of a curve guided solely by the current. In all these cases, therefore, it will be found (sometimes inexplicably unless with these considerations) that the boat insists upon passing between A and C, where it must not be allowed to go on the hypothesis we have started with; and if it effects a compromise by running upon C, this is by no means satisfactory.

This class of cases includes all those in which the river makes a quick turn round a rock or a tongue B, where the boundary formed by the rock A on the outer bend of the stream is a solid bank, or a fringe of growing trees, or of faggots artificially built as a protection against the erosion of the water. This case occurs, therefore, very frequently in some fast rivers, say, at least, a hundred times in a day's work, and perhaps no test of a man's experience and capacity as a canoist is more decisive than his manner of steering round a fast, sharp bend.

The tendency of the canoist in such cases is always to bring the boat round by paddling forward with the outer hand, thereby adding to the "way," and making the force of the current in its circular turn less powerful relatively. Whereas, the proper plan is to back with the inner hand, and so to stop all way in the direction of the boat's length, and to give the current its full force on the boat. Repeated lessons are needed before this is learned thoroughly.

The case we have last remarked upon is made easier if either A or C is a breaker, but it is very much increased in difficulty if the rock B is a breaker or is a strong tongue of bank, and so deflects the current outwards at this critical point.

The difficulty is often increased by the fact that the water inside of the curve of the stream may be shoal, and so the paddle on that side strikes the bottom or grinds along it in backing.

When the curve is all in deep water, and there is a pool after B, the boat ought not to be turned too quickly in endeavouring to avoid the rock C, else it will sometimes then enter the eddy below B, which runs up stream sometimes for fifty yards. In such a case the absurd position you are thereby thrown into naturally causes you to struggle to resist or stem this current; but I have found, after repeated trials of every plan I could think of, that if once the back current has taken the canoe it is best to let the boat swing with the eddy so as to make an entire circuit, until the bow can come back towards B (and below it), when the nose of the boat may be again thrust into the main stream, which will now turn the boat round again to its proper course. Much time and labour may be spent uselessly in a wrong and obstinate contest with an eddy.

In fig. 6, where the three rocks are in a straight line, and the middle one is a breaker, an instance is given when the proper course must be kept by backing during the first part of it.