Nowadays many of us tend to refer to single unit railcars as "Bubble Cars" especially Classes 121/122. Iris however is often refered to as a railcar.

Best wishes,

John H.T.

The ones I am on about only had 4 wheels and were not fitted on bogies.

You mean this lot that in the late 50's, British Rail tested Railbuses, produced by a variety of manufacturers.
These proved to be somewhat unreliable. The lines they worked on were mainly closed and, being non-standard, they were all withdrawn, before being allocated TOPS classifications. In addition BR ordered three for departmental service.

The full list of passenger and departmental units is set out below.
Number Range Builder Introduced No. Built Region Withdrawn
79958-59 Bristol / Eastern Coach Works 1958 2 Scotland 1966
79960-64 Waggon und Maschinenbau 1958 5 Eastern Region/London Midland 1967
79965-69 D Wickham & Co 1958 5 Scotland 1966
79970-74 Park Royal Vehicles 1958 5 London Midland / Scotland 1968
79975-79 AC Cars 1958 5 Scotland / Western Region 1968
999507 Elliot Wickham 1958 1 Departmental 1997
998900-998901 Drewry 1950 2 Departmental 1990
Number W79978 is preserved

Unreliable ?

I remember reports of passengers at Maldon having to push the railbus along the platform to "bump start" the engine.:D

I see the Colne Valley Railway have one (or more) railbusi (plural of railbus ? :))

Nice try, but the plural of railbus can only be railbuses.

Some words derived from the Latin and ending in -us can be made plural by changing the ending to -i, so railbus would be railbi; but railbus is not a Latin noun. It is formed from the prefix rail- and the suffix -bus, which is itself a contraction of omnibus, being the dative plural case of omes, all, and meaning for all. So while railbus may sound like a Latin noun of the second declension, it ain't, and can't be declined like one.

The benefits of a classical education... :confused: