Swift Boats and John Scott Russell

From the late 1830s, the way to travel between Edinburgh and Glasgow was by timetabled Swift Boat, and hundreds of thousands passengers did, by day and by night, until the railways took over a decade later.

The passage from Edinburgh to Glasgow took seven hours. Passengers changed boats at Falkirk to avoid going down the locks and horses were changed every four miles. Fiddlers, gaming tables and a library provided entertainment on board.

Fast, silent, smooth, sheltered and comfortable, far out-performing road carriages, a whole new technology had developed from the experimental and theoretical work of a young John Scott Russell, on this very canal, following up on reports of strange boat behaviour behind a bolting horse in Paisley. The discovery is described here in his own words:

“I was observing the motion of a boat which was rapidly drawn along a narrow channel by a pair of horses, when the boat suddenly stopped—not so the mass of water in the channel which it had put in motion; it accumulated round the prow of the vessel in a state of violent agitation, then suddenly leaving it behind, rolled forward with great velocity, assuming the form of a large solitary elevation, a rounded, smooth and well-defined heap of water, which continued its course along the channel apparently without change of form or diminution of speed. I followed it on horseback, and overtook it still rolling on at a rate of some eight or nine miles an hour [14 km/h], preserving its original figure some thirty feet [9 m] long and a foot to a foot and a half [30−45 cm] in height. Its height gradually diminished, and after a chase of one or two miles [2–3 km] I lost it in the windings of the channel. Such, in the month of August 1834, was my first chance interview with that singular and beautiful phenomenon which I have called the Wave of Translation.”

The two-way mix of fast and slow boats – all horse-drawn from the same path and none with brakes – led to strict operating disciplines.  A  rider with a horn preceded the fast boats to warn the others: the Swift Boat’s swan-neck bow carried a blade as a last resort.

Scott Russell’s researches revolutionised ship hull design worldwide, and the Solitary Wave phenomenon he discovered on this canal has proved fundamental in many branches of Physics.

Diagram showing the principle of Scott Russell’s “Wave of Translation” under Union Canal Bridge No 23 near Drumshoreland