Publisher's blurb: "A brief biography of Samuel Adams describing his activities in stirring up the revolt against the British and how he was finally persuaded to learn to ride a horse."
He may not ride a horse, but this book tells us Sam Adams, when afoot, is accompanied by his "shaggy Newfoundland dog" named Queue. For whether or not Adams actually owned a Newfounland — there is some slight evidence he did, and that it was trained to bark at British "redcoats" — check out this blog page.
An earlier young reader's book about Samuel Adams and the American Revolution also features Adams' Newfoundland, and is discussed here at The Cultured Newf: We Were There at the Boston Tea Party by Robert N. Webb (1956).