British naval and land units arrive to defend Campobello Island from a Fenian Raid
In the preceding days, hundreds of New York based Irish nationalists had gathered around the northern coast of Maine with the intent to seize Campobello Island in British Canada to create a diversion to aid a Fenian uprising in Ireland. U.S. officials intercepted the Fenian arms shipment and when H.M.S. Duncan arrived with 700 British regular troops aboard, the poorly conceived and executed endeavor faded out. (By John Osborne)
Hereward Senior, The Last Invasion of Canada: The Fenian Raids, 1866-1870 (Toronto, Canada: Durndurn Press, Ltd., 1991), 50-56.