I recommend downloading offline Wikipedia to your smart phone
or tablet. There are a number of free and paid apps available. They download the print version for you without photos so it doesn't take up that much space.
A great resource to have on board which we used a lot more than I expected on our crossing last year, fortunately to resolve trivia disputes and for learning
about the ocean and wildlife and not as a medical resource.
I think as a medical resource it is a great tool to supplement your other reference materials. Useful for a second or third opinion or learning
about drugs or conditions beyond the scope
of most medical manuals
Also a nice aid to relive Internet
withdrawal if you suffer from that particular affliction.