"Robert Woolley" wrote in message
news
On Wed, 6 Aug 2003 18:39:45 +0100, "Clive D. W. Feather"
wrote:

Attached to various sleepers at High Street Kensington there are a
number of data plates. Presumably these can be found all over the
system. There are two main types (plus some odds and ends).

One sort has a large arrow and gives the name of the station and the
track. There's one at the start of the platform, and others along it
with relative distances marked.

The other sort has a large arrow as well but has various items written
on it. Here's an example:

R C C.G.
305 30
$26 $
STR NIL + 6m

I'm thinking that those letters are indication of some imperial measurement
of length. R is probably Rood or Rod. 1 Rood is 3.77 metres, 1 Rod is 5.03
metres. C could be Cable, of which one is 185.31 metres, or Chain. There are
two types of Chain, Ramsden and Gunter, 30.48 and 20.11 metres respectively.
C.G. is likely Chain Gunter. Arrow could be distance to some certain point
from that plate.

HTH,

Marcus