An assembly of Leyden jars to form an electric battery. From the 1773 French edition of Benjamin Franklin’s “Experiments and Observations on Electricity.” In the public domain.

An assembly of Leyden jars to form an electric battery. From the 1773 French edition of Benjamin Franklin's "Experiments and Observations on Electricity." In the public domain.

An assembly of Leyden jars to form an electric battery. From the 1773 French edition of Benjamin Franklin’s “Experiments and Observations on Electricity.” In the public domain.