THE ERUPTION OF AIOUXT KATMAI 



161 



nel-shaped cloud, which rose straight 

 into the air to a considerable altitude, 

 and, as there was no wind, retained its 

 shape. It afterward assumed different 

 colors and dissolved into cloud banks, 

 being illuminated all the time. A similar 

 cloud was observed from Iliamna, 115 

 miles north-northeast of the volcano and 

 135 miles from Naknek, at the same 

 time, the description differing from the 

 above only in the statement that in losing 

 its funnel-shape form it assumed "the 

 shape of a ship." 



A severe earthquake was felt in the 

 Yukon Valley and Alaska Range on Jul>' 

 6, the after eft'ects continuing for about 

 a week. It was apparently not felt in 

 southwestern Alaska, and it is very 

 doubtful whether it has any connection 

 with the volcanic disturbance, as it was 

 apparently central to the north of IMount 

 McKinley. 



Strong sulphurous fumes were re- 

 ported by several on board the Maniiiiig 

 from 6 to 9 a. m., July 27, when south of 

 Marmot Island and about 120 miles east 

 of the volcano. The author did not notice 

 the fumes, but they were of sufficient 

 strength to darken the new white-lead 

 paint on the Manning and in Kodiak. 



An immense column of steam ascend- 

 ing through the ordinary clouds in the 

 position of Mount Katmai was seen by 

 the writer during the evening of August 

 12 from Takli Island. While anchored 

 here we heard almost continuous roar 

 as of waterfalls or of surf on the islands, 

 but no such surf was seen. Possibly 

 the sound came from landslides in the 

 ash, but more likely from the volcano. 



THE RAIN THAT TARNISHED SILVER 



On August 15 the writer was at the 

 mouth of Katmai River. The wind was 

 from the west and the sky was clear 

 much of the day, except for cloud caps 

 on the mountains. 



The hills from west (magnetic) around 

 through the north to the east (magnetic) 

 of Katmai village were enveloped in a 

 blue haze, which became denser through- 

 out the morning. At noon the haze be- 

 came so thick that the end of the ridge 

 north of the Steamboat Bay \'alley and 

 the low hill 2 miles northwest of Kat- 



mai village were invisible from our an- 

 chorage, a mile above the mouth uf the 

 river. 



Rain fell during the middle of the 

 morning. The drops of water striking 

 the eyes produced a sharp pain, and brass 

 and silver were tarnished by the drops. 

 The blue haze was thickest about noon 

 and came nearer with the stronger wind, 

 receding as the wind lightened. About 

 I p. m. it became oppressively sultry, an 

 apparent glare of heat being noted from 

 the north. Xo sounds attributable to the 

 volcanoes could be heard, nor were earth- 

 quakes felt. Photographs were taken, 

 showing the edge of the haze on the end 

 of the ridge west (magnetic) of our an- 

 chorage. No clouds over the volcanoes 

 could be seen on account of the haze. 



On August 16 sulphurous fumes were 

 noted by H. M. Eakin i.t the Ophir Creek 

 mines, 350 miles north of the volcano. 



On August 17 earthquakes were felt 

 at Naknek. They were so violent as to 

 upset lamps on the table. Reports either 

 of thunder or explosions were also heard. 



COMPARISON WITH OTHER ERUPTIONS 



The magnitude of a volcanic eruption 

 is not properly measured by the loss of 

 life and damage to property which it 

 caused, for these are the accidental re- 

 sults of the eruption and are due largely 

 to the chance proximity of cities. It is 

 rather to be measured in terms of the 

 natural phenomena ; the quantity and dis- 

 tribution of the ejected material, the dis- 

 tance at which sound waves, dust, dark- 

 ness, and fumes were observed, the vio- 

 lence of the accompanying earthquakes, 

 the distribution and intensity of the re- 

 sulting atmospheric conditions, and other 

 natural phenomena of various kinds. 



The greatest eruptions on record, meas- 

 ured by criteria of these kinds, include 

 those of Krakatoa in 1883, Cosoguina in 

 1835. Tomboro in 181 5. Skaptar-Jokull 

 in 1783. and Papandayang in 1772. The 

 eruption of Katmai was apparently of a 

 magnitude comparable with some of 

 these (see article by Dr. Abbot in this 

 number). 



Comparing the eruption of Katmai 

 with that of Krakatoa, in Sunda Strait 

 between Java and Sumatra, in 1883. we 



