Engineering Wonders of the World
Volume I

THE UGANDA RAILWAY. 63 AT MILE 481. ning through a tropical or semi-tropical coun- try, the Uganda line has suffered severely at , one time and another through Wash = outs. these wash-outs, which often carry away the track for a considerable dis- tance. They are caused by the torrential downpours of rain that take place at certain seasons of the year beating against the side of an embankment, and so loosening the earth that finally it collapses, carrying the line with it. Efforts are constantly being made to pre- vent these wash-outs by the construction at frequent intervals along the track of culverts large enough to carry away the rain in any conceivable quantity. So much work has now been done in this direction that it is hoped that all danger of wash-outs has dis- appeared. Another curiosity of this wonderful line is the telegraph poles that skirt the railway for a considerable portion of its route. On the upper sections of the railway Living Telef,,^ wag yie cos^ of graph Poles. iron poles, such as are being used on the trans-African telegraph wire, were too expensive to erect at first, so wooden poles were substituted in their place. A difficulty, however, quickly rose. White ants, one of the most destructive insects known, which literally swarm in these regions, seemed to have an insatiable appetite for the wood of the poles, and speedily honeycombed those erected until they collapsed, carrying the wire with them. The engineers were greatly puzzled for some time to find some means of circumventing the ants ; but at length they discovered acci- dentally the curious fact that the insects rarely or never attacked living trees, presumably on account of the sap, which is fatal to them. It was decided therefore to transport numbers of trees from the forests close at hand to the edge of the line, and to carry the telegraph wire along the upper branches of these. The “ bark cloth ” tree was principally selected as being the most suitable, since it bears transplanta- tion very well, and is very plentiful in these districts. The wire is bound to the trees by lengths of ordinary tarred rope, and, save for a periodical lopping of the lower branches, these living telegraph poles require little or no atten- tion. From whatever point of view the Uganda Railway be contemplated, it stands as a monu- ment to British skill and British, enterprise. The ingenuity shown in surmounting the many difficulties encountered was truly remarkable, A ROCK CUTTING.