These two opage show  the document issued by the local licensing authority when a vehicle was first registered for use on the road, usually when new (*). The details of the vehicle were entered on page 8 as below;

Registration mark -   TOK  258
The Taxation class -. Private / Goods /Heavy goods /PSV
Make -   Self explanatory
Type of body -  sports/saloon / station wagon/ p/up / etc
Propelled by - Petrol / heavy oil (diesel)/ gas/ electric traction.
Manufacturers type or model - +8  / 4/4 etc
Chassis frame or car Number - Self explanatory
Engine number - self explanatory
Rating - initially in HP, superseded by CC  (taxation classes were
initially by HP, more HP more tax, set up  in pre-defined groups)
Seating capacity - (Often not filled in on private vehicles More for PSV...
Public Service Vehicles, busses and the like.)
Unladen weight - Again not for cars, more for goods vehicles
Date of original registration - When it was first registered for the road.
Space for stamp of the licensing authority who first registered the vehicle.

*  Not all vehicles were new when first registered as we commonly know in
the case of Morgans also some cars would be imported and some may have been
race cars for a few years, there are many scenarios.

Pages 9&10 had sections to record the annual road tax payments at the local licensing authority, this usually was achieved by waiting in a long cue at the local office and paying over £s in exchange for a paper disc which fitted to the inside of the screen (not to have it displayed is an offence) and a an official stamp in the book to confirm payment there are 28 spaces on which this transaction could be recorded, there were shorter terms of taxation available than one year, I think they ran in quarters, though now
the minimum period is six months.

When buying a car you would ask to see the log book to check all the relevant details, car details and the number of previous owners and who they were, and if the deal went ahead , you had to go to your nearest licensing authority to have your details recorded, and if the car was bought from another Licensing authority area than your local authority would add it`s stamp to page 4 and inform the previous licensing authority that the car now fell under it`s Juristiction.