Archive Assistant Robert Lee takes a look at one of the many small interactions that went into the creation and updating of the Ordnance Survey maps that we know and love.
Between 1791 and 1845, The Board of Ordnance had commissioned a mass triangulation survey of Great Britain; endeavouring to produce a “grand meridian line, thro’ the whole extent of the Island” (Roy). Such an endeavour would fine tune the latitudes and longitudes of the country, and allow for more accurate mapping. Approximately 300 obelisks, all ostensibly placed on some high point, like hills and mountains, were plonked around Britain, upon which triangulation would be undertaken. Not all of these points were natural, however.
I have uncovered a letter (D/P 263/6/26), sent on behalf of the Ordnance Survey Office, to a church in Ardleigh, Essex. The letter warns vehemently, yet with a hint of irony and sympathy, of the need to occupy the church’s roof once more for a re-triangulation survey in 1938. “[I]t will be necessary”, the correspondent expounds, “to carry out most of the observations by night from and to small electric projectors”.
There is something beautifully modernist about the vignette of several
Ordnance Surveyors perched atop a church tower in a small county parish,
operating a heavy laser projector between old stone pinnacles. No more apparent
is the imminent crossover between old-time religion and contemporary science.
There are still tickets left for our
forthcoming conference, Playing to the Whistle: the Railways of Essex and
East Anglia, which is being held on Saturday 1st April. This
will cover several aspects of the history of railways in our area along with a
talk on how to make a steam engine in the 21st century. Graham
Rowlands of the Holden F5 Steam
Locomotive Trust, who will be speaking at our conference, shares some
information about the project:
“The Holden F5 Steam Locomotive Trust was formed in 2003 with the
objective of constructing a replica of the Great Eastern Railway’s M15R
(latterly LNER/BR F5) Class of locomotives. With examples to be seen throughout East
London and East Anglia, the last members of this type were withdrawn and
scrapped by 1958. In their last years of service, they became synonymous with
the Epping to Ongar branch where they operated push-pull services until
The Holden F5
Steam Locomotive Trust was a spin-off from a preservation group, who had the
aim of preserving the Ongar branch in Essex, after the realisation that
suitable locomotives from the Eastern region barely existed. Whilst not
the grandest of locomotives, upon completion the engine will be well-suited to
the needs of many heritage lines; with modern engineering practices and design
work being coupled with original drawings, GER 789 will be more than capable of
all but the heaviest loads.
To date, The Holden F5 Steam
Locomotive Trust has had a number of components manufactured including:
cylinder block, smokebox, chimney, machined wheels, plus much more besides. The
main frames have been assembled at the Tyseley Locomotive Works in Birmingham
and support the finished coal bunker and smokebox. Major progress WILL
be made in 2023.”