from the great fall in the tide, which at spring was no less than . [He] was of opinion that by a train being stopped, divided, and placed upon the steam bridge, and landed on the opposite side of the Hamoaze, tackled together, and put in motion, a great delay would be occasioned, independent of the seven or eight minutes in crossing, of from eight to twelve minutes on each side. Penryn The embankment across Penryn Creek was similarly ill thought through. There was to be an embankment (or viaduct) with a drawbridge to pass ships to Penryn Harbour; the waterway was tidal, of course, and the sailing ships needed sea room to beat up the channel, and needed to do so at the top of the tide. Steep railway gradients were necessary either side of the crossing. Evidence was given that the obstruction by Moorsom's embankment made it quite unacceptable, and several "memorials" had been submitted to that effect. In his evidence at the Lords Committee, Moorsom seemed to know little of the formal objections to the scheme. The atmospheric system Moorsom planned to use the atmospheric system of traction. In this system a tube was laid between the rails, and a wagon with a piston running in the tube led the train. No steam locomotive was required; stationary steam engines at intervals evacuated air from the tube. The advantages seemed considerable: there was no need to convey the weight of the engine, and its fuel and water, on the train; more tractive power could be applied than the early locomotives could provide; and head-on collisions were considered to be impossible. The system had been operating, apparently successfully, on a section of the Dublin and Kingstown Railway (D&KR) and, less successfully, on the London and Croydon Railway. It appeared particularly appropriate for steeply graded lines like the Cornwall Railway, and it was planned for use on the South Devon Railway. After an inspection of the Dalkey section of the D&KR, Moorsom reported to the Provisional Committee: I am of opinion that the system is applicable with certainty and efficiency to the Cornwall Railway. That a sufficient power may be obtained so as to work the trains, which I think your traffic will require, at an average speed of 30 miles an hour for passenger trains, and from 15 to 20 miles an hour for goods, including stoppages in both