OUR GREATEST NATIONAL MONUMENT 



249 



-m 



Photograph by R. F. Griggs 

 MOUNT MARTIN FROM THE PACIFIC SIDE 



Three times we climbed this volcano and once descended inside its crater, but in our 

 attempt to study it we were baffled by the fog, which each time shut down and kept us from 

 seeing what we sought to observe (see text, pages 269 and 270). 



quite the same frequency as in former 

 years. The old volcanoes — Katmai, Tri- 

 dent, Mageik, and Martin — also were less 

 vigorous than in 191 6 and 191 7. 



It is by no means certain, however, 

 that this indicates that the activity of the 

 region is dying out. The big volcanoes, 

 which alone were known at that time, 

 had a similar slackening in activity in 

 191 5. We could not be certain that year 

 whether Katmai was active at all, and the 

 steam from Trident could not be seen 

 except under favorable atmospheric con- 

 ditions. But the two following years the 

 activity of both these vents increased 

 measurably, so that no one would have 

 questioned' the reality of the steam clouds 

 issuing from them. 



Whether the slackening of the activity 

 of the valley vents observed in 1919 

 was simply such a temporary fluctuation 

 or whether it represented a permanent 

 quieting down can only be judged by the 

 future. In either case, there is no reason 

 to expect any sudden extinction of the 

 Smokes, for the changes observed were 

 so slight that we could not be certain 

 that there was a real slowing down of 



activity until after many days of obser- 

 vation and comparison. 



Although some signs of a diminution 

 of activity were detected around the 

 edges of the valley, the geophysicists 

 found temperatures very much higher 

 than any that had been measured be- 

 fore — higher, indeed, than any of us had 

 believed to exist in the valley. 



MEI/TING I^AD AND ZINC IN THE 

 FUMAROFFS 



It was late in the season before any of 

 these hot places were discovered, and all 

 felt that if only there had been more time 

 certainly more hot ones and probably 

 others with even higher temperatures 

 would have been found ; but the increas- 

 ingly bad weather put a stop to further 

 efforts in that direction. 



Well do I remember the excitement 

 when Dr. Allen, coming in late one even- 

 ing, announced, "Three times have we 

 melted zinc this day." They had found 

 three widely separated fumaroles with 

 temperatures above the melting point of 

 zinc (419 C, 784 ° F.). The hottest of 

 these was practically five hundred de- 



