When I need to repair anything on my sailboat this is the first book I turn to. The illustrations are excellent. The book is actually six books compiled into one, which makes navigation of it a bit difficult but not impossible. The explanations are very clear with detailed information on things such as fiberglassing with resin versus epoxy, electrical wiring, and inboard diesel engines.
As a companion to this I find my subscription to Practical Sailor magazine to have up to date first hand reports on sailing equipment and products from porta potty deodorizers to bottom paints to navigation systems.
From directly forward and astern, the hull should appear symmetrical and the keel perpendicular to the deck. Sighting the hull through the gridwork of a plastic plotter simplifies this determination. Any detectable difference from one side to the other suggests major trouble. (p 11)
A more insidious problem is galvanic corrosion. Connecting the green wire to an underwater fitting completes the circuit between your boat and all other nearby boats with their own green wires grounded. With seawater as the electrolyte, every grounded fitting essentially becomes part of a big battery. (p. 557)
If your fittings are less noble on the galvanic scale than your neighbor’s, they are anodes and begin to erode. This can be bad news if you have an aluminum outdrive in the water and your neighbor’s underwater fittings are bronze and stainless steel.