This is a questionable event.
|Start:||October 11, 1826 ||Observed|
|Stop:||January 1827 ||Observed|
|Tephra plume: ||
|"Fire", "Glowing", or incandescence: ||
|Duration: ||Ash fall for at least 10 days ||
|MaxVEI: ||3 ||
Khlebnikov (translated in 1994) writes of a volcano that is possibly Fisher caldera: "On 12 October 1826 the crest of another mountain [not Shishaldin or Isanotski] on the southwest side of the island [Unimak] was ruptured with horrible thunder-like noise, throwing out a lot of ash which was carried by the then blowing east wind and dropped over various places on Unalashka Island. The residents of Unimak Island sat in their yurts for ten days with lights, because it was impossible to go outside because of the blowing ash, which, entering the eyes and nose, caused an unbearable headache. During all this time, no daylight was visible. The condition of the atmosphere at that time would have given an amateur observer an understanding of atoms."
Veniaminov (1840, translated by Lydia T. Black and R.H. Geoghegan, 1984) also writes: "On October 11, 1826, with a dull noise, it [the low peak in the interior of Unimak Island] burst, emitting strong flames and a large quantity of ash of whitish color, which covered part of Aliaksa, Sannakh, and the islands closest to the latter, and was carried even to Unga. (This same ash caused the destruction of the wild pigs on Chernoburyi Island and the decrease of the caribou.) Since that time, the scattered large, extremely hot rocks, which lie about in heaps, have emitted incessant smoke. Around this peak burning sulphur may be found. All streams and swamps about this area are so hot that they steam constantly."
Subsequent compilers have used Veniaminov's October 11, 1826 date as the start of the eruption rather than Khlebnikov's October 12 date.
Stelling and others (2005) state: "The most likely deposit related to this eruption is a thin, fine-grained, black scoria within the vegetation mat distributed across the central portion of the caldera. The fresh apperance of the summit of Mt. Finch and the limited dispersal of the scoria layer suggest that the eruption emanated from this cone."