Itareus - as a matter of interest where did you get that info on the bridge and does your source also cover the Malton & Driffield?
The source is "The Railway Record" a database of UK railway infrastructure which has been built up over a period of more than 30 years. It started off as a card index of stations and now covers the whole country in a level of detail down to individual buildings, culverts etc and is held in a relational database (the design and programming of which which was my "contribution"). The level of detail varies, some areas such as East Anglia are complete others are still being worked on and data is being added by a team of railway historians using reliable sources such as old engineering drawings, Bridge Registers etc. As you can imaging it's no small undertaking.
I have just checked the Malton & Driffield, it is covered down to fine detail - Stations, Culverts, Occupation Crossings, Ground Frames, You name it! All with mileages.
This data is not yet publicly available - there is talk of a website but don't hold your breath! I could ask my friend who "controls" the database if he will send you what he can on the M&D if you like. He will have the most up to date data and possibly even some photos (although copyright issues may come into play with these).
Ben,
Having seen the photo I'm now sure this is the River Derwent Viaduct"
"Steel girders, stone abutments, 3 spans - 43ft 1in, 73ft 10in, 39ft 10in, max headway 30ft 9in"
Chris