Interesting concept. Clearly an Official document. I recall my Boat-work logbook from Dartmouth which was vaguely similar ... with piquant comment from Bob McQueen about not using the same colour ink, etc.
Sadly neither my eyes nor linguistics take me any further, but I get the concept. One is a simple record of 'hours', if you will, and the other is 'what happened today.
i used to have to generate this sort of 'cr@p'
