This folder contains correspondence and other documents relating to Edison's opinions about harnessing hydraulic power from tides. Included are items pertaining to Edison's endorsement of a power system proposed by inventor Thomas A. MacDonald. Among the correspondents for 1912 is Harry C. Webber, editor of the Bath Independent in Maine.

Less than 10 percent of the documents have been selected. The items not selected consist primarily of unsolicited correspondence seeking Edison's advice, information, or assistance on technical or financial matters relating to tidal power. These letters received no response or merely a perfunctory reply from the inventor.