Once again, I'm afraid, I have written to you concerning a misapprehension in Looking Back, 'Well-trod Feltham path' (Chronicle, October 16).

Eddie Menday reports that the Union Construction and Finance Company (UCC) factory in Feltham closed because 'more manouverable trolley buses took over the (tram) routes'; this suggests that UCC had only ever built trams and that, with no further requirement for new trams, there was no other work.

In fact, during the period 1928-1931, UCC built, in addition to 103 'Feltham' tramcars, 241 carriages (always referred to as 'cars') of 'Standard' stock for the Underground group (incidentally, these included the first to dispense with the centre pillar at the door openings and incorporated single end-doors for the first time, both major innovations), and 60 trolleybusses for London United Tramways (the A1 and A2 Classes, known as 'Diddlers', a familiar sight for many years in the Twickenham/Teddington/Kingston areas).

Thus, there was scope for continuing construction of tube cars and trolley buses so the reason for UCC's demise lay elsewhere.

The company was a venture of the Underground group set up in 1909 but it lay dormant until the late 1920s when, with the involvement of two tram-operating companies, it was brought into life.

There is no doubt that it would have continued to prosper had it not been for the 1933 London Passenger Transport Act which set up London Transport as the overall provider of all public transport in the London area from July 1, 1933.

One of the clauses in the act prohibited the construction of road and rail vehicles (except for those deemed to be experimental, work on which was mainly carried out at Chiswick Works) and this spelt the end of UCC; this prohibition was a sop to the other tube car and bus/trolleybus constructors who feared that London Transport would allocate most of the new-build work to an enlarged UCC and deprive them of a huge market.

DEREK WHEATLEY Whitton Dene, Isleworth