APPENDIX I. 339 As already mentioned, the ordinary baggage animals are useless on account of the tsetse fly, though, it is true, it has been suggested that possibly a line of country might be found north of the 7th parallel of S. latitude where this fly would not be met with ; but this is far too vague an hypothesis on which to found any project.

The only alternative, i;hen, seems to be some kind of railway ; and I feel, for my own part, convinced that Central Africa can only be opened up by steam-power. It would be premature for any one to say that any particular kind of railway was the one for Central Africa ; but of all those I have seen or read of, that described by Mr. J. B. Fell, in a paper read before the Society of Arts, on April 29th, 1879, seems to me the best suited for Africa. One of its great advantages is that it obviates the necessity of having large embankments or deep cuttings, the rails being carried over the inequalities of the ground on viaducts of wood or iron, much, I imagine, like the American trestle bridges.

Such a railway, which would cost only a small amount per mile for construction, which could be laid with tolerable rapidity, and which would admit of moderately heavy trains running at a speed of from twelve to twenty miles an hour, would do wonders towards opening up these regions to commerce.

In laying the line of rail the neighbourhood of large rivers should be avoided as much as possible, as they change their beds and alter their course so frequently and with such rapidity during the rain, that they would carry away the track completely on either side of their beds, and thus necessitate the relaying of large portions of it after each rainy season, besides suspending communication altogether for a considerable period.

The route for such a line should also be, as far as compatible with directness and slight gradients, through an inhabited district, so that trade might at once be begun with the natives. For my own feeling is that it would be very unwise to attempt to carry the line of rail at first as far as the Victoria Lake. A line of 100 miles or so in length would connect the East Coast range of mountains with the seaboard, would open up a considerable area of country to commerce, and z 2