Tom Anderson wrote:
On Sun, 27 Feb 2005, Jack Taylor wrote:

SWT diagrams are becoming thinner by the week. The Windsor lines
became Desiro-worked at the beginning of December but several of
the Portsmouth/Haslemere diagrams remain CIG/VEP. I haven't got an
up-to-date list of current diagrams but, at the beginning of the
year, the following diagrams *out* of Waterloo were slam-door:

So, what exactly is a diagram?

The original railway usage is "a graphical schedule for operating
railway locomotives and rolling stock in order to provide a desired
service" [New Oxford Dictionary of English, 2001]


There's a simple example of a service that uses 4 trains at
http://perso.wanadoo.fr/cf-chanterai...is/exploit.htm
(scroll down to "diagram of timetable").

The term is often used nowadays (as in Jack Taylor's post) to refer to
the set of journeys allocated to a single train formation over the
course of, typically, one day.
--
Richard J.
(to e-mail me, swap uk and yon in address)