The original big clock at Highbury was placed at the rear of the then uncovered Laundry End of the ground (which later became the North Bank), on or around 10 September 1930. Pictures from the time show the clock having a 45 minute face. Commentaries in newspapers stated that the end of each half would be announced by a klaxon and that the clock measured 8 feet 6 inches across.
Thus fans the majority of whom at that time would not have their own watch, were able to see how much time there was left in each half. (There being no substitutes, and fewer visits from medical staff, interruptions were fewer, and so halves really did last 45 minutes, and 3pm kick offs did end at 4.40pm. As people left the ground newspaper vendors were to be heard shouting, “All the half-times, 3.30 winners”).
However the Football Association felt that this ticking of 45 minutes would provide far too much information to the fans, would distract them from the game and undermine the credibility of the match officials. Thus Arsenal were ordered to remove the clock.
However the FA’s injunction was itself not explicitly and so Arsenal responded by changing the clock so that the clock face showed the normal time of day – which worked just as well, because of the strict regularity that of ten minutes for half time, and no time added on for injuries.
The FA took no more action and the clock remained at the rear of the terracing until 1935 when it was decided to cover part of the Laundry End (later known as the North Bank).
With the College End of the ground opposite, remaining uncovered, the clock was placed at that end, and this quickly became known as the Clock End.
Different clock companies were charged with maintaining the clock which did actually break down occasionally, and by the time of the move to the Emirates it was in the hands of Smith of Derby.
When Arsenal FC moved from Highbury to the Ems, the club claimed that the original clock on the south bank was saved and moved to be put on the stadium outer wall facing what then became the Clock End Bridge over the railway. However, there is the strong claim also made that the clock that transferred to the Emirates only made its debut at the start of 1989 – but somehow the Club has always passed it off as the original.
The Islington Gazette however reported that one of their staff had seen the clock in pieces and that a new clock replaced it, with a similar, but not identical clock. The move of the clock took place on 27 July 2006 and this Highbury clock was lifted into its new home on the wall of the Emirates by a 25 tonne crane and took four people nine hours to install.
After the removal, Smith of Derby also built a half-size (ie 1.3m diameter) replica of the clock which is placed in the Diamond Club within the stadium.
Then on 21 August 2010, ahead of the home game against Blackpool, a new version of the clock, suitably scaled up in size to be appropriate to the Emirates was unveiled at what was the South End of the ground, and this quickly became renamed as the Clock End.