Most people have a treasured childhood memory of a favorite soda drink — or "tonic" or "pop" depending on what part of the country one lives — along with that fizz that occurs when the container is first opened. For many Cape Ann residents, Twin Lights soda was their go-to choice as temperatures as began to rise.

In a new book, Rockport resident Paul St. Germain and Devlin Sherlock share the story of a local mom-and-pop soda operation, and place it into a historical perspective of the nationwide soda industry.