Viruses as a concept are just a little younger than bacteria - they were first described only in the 1890s - yet have probably co-existed with cellular life through nearly the whole of evolutionary history on this planet.
This book will give an account of the history of the discovery of viruses, with some case studies on particular aspects, concentrating on the technological developments that were necessary for the discovery events to happen.
A Short HIstory of the Discovery of Viruses
For someone like me, parachuting in to try to quickly grasp the history of virology, this book is a godsend. Accessible and well-organized, it gives enough information without overwhelming me with too much. The links point me to where I can find more if I need it. And the art is fantastic. I can't recommend this book too highly.