I presume you mean the picture on pages 116/7 at the start of the Freight Rolling Stock section.
The 'Open Coal Deposit' - known best in the North of England as a 'staithe' - was above ground level so that the coal, emptied through a trap-door in the bottom of a wagon, was then easily accessible to be loaded into sacks, weighed and put on a lorry. There are a few examples still about, noticeably at Goathland on the North Yorkshire Moors Railway (which is also the prototype for R8629 Station Building on page 148 of the 2006 catalogue), and remains at Shildon, now the 'Locomotion' museum site, although here it is only the stone piers left.
Because only a few wagons would be moved onto the staithe at a time, and at low speed, there could be short but fierce gradients leading up onto them. Or as at Goathland the lie of the land would be used to minimise the gradient needed.
Hope this helps.
John Webb
The 'Open Coal Deposit' - known best in the North of England as a 'staithe' - was above ground level so that the coal, emptied through a trap-door in the bottom of a wagon, was then easily accessible to be loaded into sacks, weighed and put on a lorry. There are a few examples still about, noticeably at Goathland on the North Yorkshire Moors Railway (which is also the prototype for R8629 Station Building on page 148 of the 2006 catalogue), and remains at Shildon, now the 'Locomotion' museum site, although here it is only the stone piers left.
Because only a few wagons would be moved onto the staithe at a time, and at low speed, there could be short but fierce gradients leading up onto them. Or as at Goathland the lie of the land would be used to minimise the gradient needed.
Hope this helps.
John Webb