It looks like a very meaty ruleset for its slim 50 or so pages, chock full of nautical crunch to satisfy the barnacle-clad old salt in you. In terms of complexity it may rank alongside Birnie's "Action Under Sail". If you're looking for a simple beer-n-pretzels kinda game, this may not be it. However if detailed ship-to-ship combat and realistic manoeuvres are what you crave, then "Heart of Oak" is the naval wargame for you! The scan is mediocre at best with some pages' text looking a bit pale and hard-to-read, and a labelled diagram of a full-rigged ship is poorly reproduced and may not be helpful unless you're already familiar with the maritime jargon. The period illos are too dark in the scan and it is hard to discern the subject-matter of the pictures, making them nothing more than a waste of printer ink. As I printed the PDF, some of the last few pages refused to print at all save for the watermark. Perhaps the maker of this PDF file can post a new, improved version that does not have problems in the printing process.
[4 of 5 Stars!]