Pere Grapi graduated in chemistry from the University of Barcelona in 1975. He later obtained a master's degree in the History of Science from the Autonomous University of Barcelona in 1990, before completing his PhD at the same university in 1996. Spending some periods working as an Associate Professor of the History of Science at the Autonomous University of Barcelona, he is now an independent scholar whose main research interests are focused on the history of chemistry during the late 18th and early 19th centuries, as well as on the relation between the history of science and teaching. Grapi is also an affiliated member of the Centre for the History of Science of the Autonomous University of Barcelona and member of the Council of the Catalan Chemical Society. The idea for this book came about when Grapi was working as an advisor for a research paper conducted by three of his final year high school students during the academic year of 2003-2004. Inspired by their research into making a replica of Volta's pile and reproducing some of the accompanying historical experiments, Grapi became increasingly interested in exploring the emergence of electricity in the practice of chemistry. He, therefore, felt obliged to familiarize himself with the contributions of prominent figures such as Volta and Priestley. Notably, both Volta and Priestley made important contributions to the development of eudiometers. Thus, quite unwittingly, it was those three former students who remade Volta's pile that motivated him to focus his attention on eudiometers rather than other chemical apparatuses. However, it wasn't until his retirement from science teaching in 2012 that he was able to dedicate the time required to complete this book.