Description: From Veniaminov (1840, translated by Lydia T. Black and R.H. Geoghegan, 1984), writing of Shishaldin Volcano: "[T]oward the end of 1824 and early in 1825, up to the 10th of March, that is, until the explosion of the Issanakhskii Range, it was burning with a fierce flame." Although Veniaminov writes that the eruption of the 10th of March was from the "northeast range of Unimak" and that "Shishaldinskaia sopka, located not far from this range on the west, emitted flame before this time, but after the explosion began just to smoke," suggesting that the March 10, 1825 eruption was not from Shishaldin, and perhaps from Isanotski, Alaska Volcano Observatory geologists now believe that this eruption did come from Shishaldin. Alaska Volcano Observatory geologists flying over Isantoski in 1987, 1988, and 1989 failed to find any apparently Holocene vents on Isanotski, and saw only glacially polished rocks. Field investigations of Shishaldin, however, reveal numerous Holocene vents, including a very large flank feature called "The Blister" that has melted through the modern ice cover of Shishaldin, and which could be the vent for eruptions during the 1800s. In addition, several streams draining from Shishaldin look capable of carrying large amounts of sediment to the sea (as described by Veniaminov for the March 10 eruption), but all of the streams draining Isanotski are heavily vegetated, suggesting that they did not carry large amount of sediment within the last few hundred years (Chris Nye, personal commun., 2004). Finch (1934) and Grewingk (1850, translated 2003 by Fritz Jaensch) also believe that the March 10 eruption occurred at Shishaldin.
Veniaminov's description of the March 10, 1825 eruption is as follows: "On March 10, 1825, after a loud subterranean thunder very similar to a cannonade, which lasted almost the whole day and was audible on Unalashka, Akun, and the tip of Aliaksa, in the middle of the day, the northeast range of Unimak exploded in five or more places and a great quantity of black ashes which covered the whole end of Aliaksa for several inches. At nearby Aliaksa, and especially at Morzhevoskoi settlement, it was dark for 3 or 4 hours. On this occasion the ice and snow, lying on the range melted and for several days flowed in a dreadful river, 5 to 10 versts wide. These waters poured over the eastern side of the island in such a quantity that the nearby sea remained muddy until late autumn."
From Grewingk (1850, translated 2003 by Fritz Jaensch): "In the year 1824 and early in 1825 the eruptions of Shishaldin Volcano were especially violent (cf. Lutke's p.n., or Berghaus: Geography and Ethnography, II, p. 724). And toward the middle of the month of March, a low ridge NE of this mountain split open in five or six places after a terrible subterranean detonation that was heard on Unalaska Island and on Alaska. Flames and black ashes were expelled, which covered the Alaska Peninsula all the way to Pavlof Bay. At high noon it was dark as night even in Morzhovoi Village, 10 German miles away. At the same time a flash-flood [jokulhlaup] descended from the mountain, down the south side of the island, covering a section of land more than two German miles long, as it catapulted pumice stones along with it. But the flood did not last long. Even the waters of the ocean were murky far into the autumn season. Since that event the volcano has burned less strongly. The ridge, through which the subterranean powers released their pressure, continues to smoke constantly; likewise a small cone, which began to rise from the middle of the ridge."