from The Century Dictionary.
- noun In a slide-valve steam-engine, the name given to each of two oblong passages from the steam-chest to the inside of the cylinder, which afford passage to the steam to and from the cylinder, and act alternately as an induction-port and an eductionport. See cut under
- noun A passage for steam into or out of any inclosure.
Sorry, no etymologies found.
The object of using a cam instead of an eccentric is to enable the opening of the valves abruptly at the beginning of the piston stroke, maintaining a uniform steam-port opening during nearly the entire length of stroke, and as abruptly closing the valves at the termination of the stroke.
The operation of the groove is to accelerate the motion imparted from the eccentric to the valve at one part of the latter's travel, and retard it at another, the accelerated portion being during the opening of the port for steam admission, and during its closure for cutting off, which enables the employment of a smaller steam-port than would otherwise be the case.
The steam-port is exceptionally large, being one-fourth of the piston area.
These, aided by its happy situation, will soon render it a great steam-port, and obliterate, it is to be hoped, the remains of the squalid borough, which traces back its foundation to the times of Saxon sea - kings.
(the steam-port leading to the right-hand end), and the movement of S 1 opens N 1 (the steam-port leading to the opposite or left-hand end), at the same time the movement of V opens the right-hand end of this cylinder to the exhaust, through the exhaust ports X and Z.