Database: Doctors (Assassin's Creed III)

During the Revolutionary War, medical knowledge and practices were only beginning to evolve to what they are today. Doctors and nurses were rare, often lacked formal training and very few of them had any sort of specialization. Treatments were rudimentary for the most part, and there was still heavy reliance on bleeding to treat infections. (I trust I don't have to tell you that doesn't work very well at all.) The instruments they used probably didn't look much different from torture devices - which makes them sound a bit like a visit to the dentist, really.

Of course, there were people who began to take a deep and genuine interest in the application of scientific principles in pursuing knowledge of medicine. They would document and share information with their peers to increase the collective knowledge - generally a good idea - which led to a general increase of the quality of diagnosis and treatments. Unfortunately, things only improved very slowly, so if you're thinking of just popping in because you're feeling under the weather, it might be best to wait a century or so.