Black and white lantern slide copy map of the Upper Geyser Basin of Yellowstone National Park from an unknown source.

Black and white lantern slide copy of the Yellowstone Park Map from a 1939 guidebook.

Black and white lantern slide of the Twin Lakes, Yellowstone National Park. Taken from the summit towards the northeast entrance.

Black and white lantern slide of the Yellowstone Lower Falls taken from the Uncle Tom Trail.

Black and white lantern slide of a natural bridge rock formation on an upper beach of Lake Yellowstone.

Black and white lantern slide of Robert Merrill standing next to the Lone Star Geyser Cone in Yellowstone National Park.

Black and white lantern slide of the Old Faithful geyser in eruption taken from Observation Point in Yellowstone National Park.

Black and white lantern slide of the Liberty Cap rock formation in Yellowstone National Park.

Black and white lantern slide of Lena Merrill standing in front of a boulder in Yellowstone National Park.

Black and white lantern slide of the Fish Pot hot spring in Yellowstone National Park.

Black and white lantern slide of Roaring Mountain in Yellowstone National Park.

Black and white lantern slide of rock formations at the Silver Gate site in Yellowstone National Park.