Glossary Results for prefix "pa"
|P4 system||See Model Gauges.|
|Pacific Wheel Arrangement||A generic name for the the 4-6-2 wheel arrangement. See Whyte wheel arrangement.|
|Pannier Tank Engine||A tank engine whose tanks are mounted on either side of the boiler but not above it (as in a saddle tank) nor reaching to the footplate (as in a side tank). Such engines were very common on the Great Western|
|Parachute Water Tank||A water column with a cylindrical water tank mounted above it, feeding only that column.|
|Parcels Van||Normally NPCS rated, a vehicle designed specifically for the conveyance of railway or Post Office parcels, in some cases fitted with tables to enable the parcels to be sorted in transit. When such a van was used for sorting parcels, it was described in the marshalling circular as a “sorting van”. That these vans were regarded as available for general purposes is evident — some, for example in the Irish Mail, were described as “sorting van” in one direction and “parcel van” in the other.|
|Passenger Class||Compartments in carriages were designated to one of three classes. First Class was plush and well-appointed, second class rather less so. Third class was pretty basic until the Midland Railway abolished second class and improved third, effectively forcing other railways to conform to that standard|
|Passenger Train||A train for carrying people. Essentially this required the vehicles in the train to meet higher standards of running gear (when compared to a Goods Train) and to be fitted with continuous brakes.|
|Patent 2-2-2 Locomotive Class||In 1852 McConnell produced his ‘Patent’ 2-2-2s to work the London–Birmingham trains in two hours. They had outside bearings and the boiler was pitched very low, with a recess to accommodate the cranks and upward inclined cylinders. The ‘patent’ feature was the design of the firebox which had a combustion chamber to burn coal instead of coke.|
|Pavior||A person who laid the flagstones and kerbs on the pavements.|
|Pennsylvania||A locomotive of the “Teutonic” class, ordered by the Pennsylvania Railroad for a trial of Webb’s compounding system. Various locomotive builders objected, successfully, that as a Railway Company the LNWR was entitled to build locomotives for itself but not to trade in locomotives.|
|Permanent Way||The track of a railway line; the ballast, sleepers and rails. This term distinguished it from that laid temporarily during construction by the contractor for ferrying materials along the length of the works.|
|Permissive Block Working||A system of train operation where, under special conditions, a train may proceed with great caution into a block section already occupied by another train. This system would be used at terminus stations to allow a locomotive to enter a platform already occupied by coaching stock, but would normally be used on through lines only when one goods train is following another. (see also absolute block).|
|Picnic Saloon||Carriage intended to convey private parties on day excursions, and so laid out with seating, tables and often a larder cupboard so as enable the party to consume their picnic food while travelling. Popular from about 1890 to 1930, but displaced by road motor coaches.|
The LNWR did not construct any special vans for pigeon traffic, but from about 1908 a number of existing six-wheeled Parcel Sorting Vans were altered to Pigeon Vans. This simply involved the provision of additional shelving.
Further conversions (perhaps the majority) were made after 1915 when many thousands of homing pigeons were bred and used for communications purposes.
|Pin Down Brakes||To apply the brakes of a goods train by pressing on the brake lever of each wagon in turn and inserting a pin through holes in a rack to keep the lever in the down position and the brakes applied, or ‘on’.|
|Piston||A disc which moves backwards and forwards inside a hollow cylinder.|
|Piston Rod||The rod that transfers the power from the piston to the Cross head and thence to the Driving Wheels.|
|Piston Valve||A type of gas-distribution valve, in which an oscillating piston covers and uncovers circumferential openings in a cylinder.|
|Plate Frame||Almost all British railway engines were built on plate frames,that is two parallel thick (c.1in – 1.25in) steel plates running front to back of the engine, in which the horn guides and axle boxes were located. cf Bar Frames.|
|Plate layer||A person who puts the track into position onto the ballast, and performs maintenance on the track thereafter. Maintenance work includes ensuring the keys are in the chairs, the chairs are firmly bolted to the sleeper; that the bolts holding the fish plates in place are firm etc.|
|Platform Trolley||A four wheeled flat vehicle with a pivoting axle attached to a tow-bar, used by station staff to move goods, mail and luggage within a station.|