Levenhuk’s informative book, “Invisible World’’ (read an excerpt), will help young scientists learn everything they want to know about microscopes and microscopic observations. They will start by learning the history of the microscope, its construction, and basic principles of working with this optical instrument. The main part of the book is devoted to microorganisms and a variety of structures that can be seen under a microscope. Cell structure, amazing bacteria, invisible E. coli bacteria; life in a drop of water – these are only a few things this encyclopedic book tells us about.