Hi yn9man
Sorry for late reply, just back from holiday..
I think you're right, not an official log-book, although that's what he calls it, more likely a diary, just one entry per day and not signed by the captain, but he does take the wheel, and describes all the things you mention, weather conditions, lat., long., compass headings, as well as what work was done, what sails and rigging, what they ate, other ships passing and their headings, all very interesting, just wish I knew who he was ...
Barbara