Sequence of photographs show second eruptive pulse on July 22, 1980. Mount St. Helens, Skamania County, Washington.

Typed caption accompanying slide: 19:01 pyroclastic flow continues its advance as helicopter moves west. Skamania County, Washington. (Photo by H. Glicken) Note: Slide numbers 43 - 50 were taken at 19:01 and show the pyroclastic flow as it advances northward. Skamania County, Washington. July 22, 1980. Slide number 51 was taken at 19:02. Slide numbers 52 - 55 were taken at 19:03. Slide numbers 56 - 57 were taken at 19:04. Slide numbers 58 and 59 were taken at 19:04 and 19:05. Slide numbers 60 - 62 are views of the eruption and were taken at 19:06. Slide no. 52, msh_vjw00052_ct, is highlighted in this photo record. Slide no. 52 typed caption: View of eruption at 19:03, the plume develops a mushroom-like head while the elutriate [...]