A Narrative of Colonel Ethan Allen's Captivity, from the Time of His Being Taken by the British, Near Montreal, on the 25th Day of September, in the Year 1775, to the Time of His Exchange, on the 6th Day of May, 1778: Containing His Voyages and Travels, with the Most Remarkable Occurrences Respecting Himself, and Many Other Continental Prisoners of Different Ranks and Characters, which Fell Under His Observation, in the Course of the Same; Particularly the Destruction of the Prisoners at New York, by General Sir William Howe, in the 1776 and 1777. Interspersed with Some Political Observations