CAN A FAST RUNNING LOCOMOTIVE CAPSIZE?

Hawera & Normanby Star, Volume XLII, Issue 7395, 22 February 1902, Page 4 (Supplement)

CAN A FAST RUNNING LOCOMOTIVE CAPSIZE?

"Engineering" says that at first sight it would seem that when a carriage is set astride on the mono-rail sys-> tern, like panniers on an ass, all chance of derailment was excluded. Not infrequently, in flying round sharp curves, such as those of the Midland Railway in the Derbyshire Dales, one has the sensation that the whole train is on the point of capsizing and rolling down the hillsides into the Derwent, and that it really needs a guide rail somewhere about the level of the seats to render it safe. That, however, is merely a mistaken interpretation of our sensations. We ("Engineering") believe that no train ever capsized yet on a properly kept road, and we have only to consider the construction of the carriage to see that the centre of gravity is so low that it is impossible that such a thing should happen. The first vehicle to go over would be the locomotive, and it is a matter of common knowledge that as speeds have increased the centre of gravity of locomotives has been raised, and notwithstanding this change they have been rendered steadier and more comfortable on the road. In spite of the high boiler barrel, the weight of the cylinders, frames, connecting-rods, etc., keep the centres of gravity low. "Engineering" published, on December 29, 1899, an account of a test made to determine experimentally in America the position of the centre of gravity in a consolidation locomotive weighing 216,0001b. - It had cylinders 23in in diameter by 30in stroke; its boiler barrel was 80in in diameter by 13ft Sin long, and its centre 9ft 2in above the rail level. Yet the centre of gravity of the entire engine, in spite of its top-heavy appearance, was only 50iin .above the rail level* or considerably below the tops ot' the wheels. It would need a speed of 132 miles per hour, round a 30chain curve, with no super- elevation of the outer wheel, to cause this engine to capsize. Of course, a moderate super-elevation of the outer rail would enable this speed to be greatly increased. Judging from his sensations, a passenger may find it very difficult to realise this, and hence, adds "Engineering," he wel' comes the idea of a railway with the centre of gravity below the rail.