The Britain from Above website has a few pictures of the Chemical Works taken in 1921 and 1932.
Note that the name Fisons was not used in 1921 it is described as 'Edward Packard and Co Chemical Works, Bramford'. By 1932 it is described as 'Fison Packard & Prentice Works, Bramford'
This 1932 picture shows the track across the road and into the quarry:
https://britainfromabove.org.uk/en/image/EPW039274
Other pictures can be found below the one linked.
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