Johnston Ridge Volcano Observatory at Mount St. Helens is named for geologist David Johnston, a scientist and one of 57 people who died when the volcano blew up.
Johnston was part of a scientific survey team examining the volcanoes' potential for an eruption. That required him to descend deep into the crater.
"What I'm trying to do is find the composition of the gases coming out of the fumaroles here," said Johnston.
"He had an unbounded enthusiasm for science, for life, for volcanoes, for friendships," said Dan Miller, former colleague and friend of Johnston.
Miller is now retired from the U.S. Geological Survey, but he worked frequently with Johnston both in the laboratory and the field.
"He also realized that gathering the information was one thing, but using it to forecast eruptions and use it to communicate and forecast volcano hazard information to the public and to government agencies was what was really important," said Miller.
David dedicated himself to that task at Mount St. Helens.
"It could conceivably produce a very large eruption, five to ten miles high by the time the eruption has risen as high as it can, sending ash as far eastwards as perhaps Yakima," said Johnston - an eerily accurate prediction.
Johnston radioed in an alert the morning of May 18th, 1980. "Vancouver, Vancouver...this is it!" he said.
Johnston's body was never found.