Black and white photograph of wooden archaeological rulers on a site of petroglyphs with shrubs and field grass in the background.

Black and white photograph of Pictured Rocks taken from a boat.

Black and white photograph of a rock formation of cliff faces on a lake. The photo is taken from on a boat.

Black and white photograph of a cliff face shoreline. The photo is taken from on a boat.

Black and white photograph of a cliff face shoreline. The photo is taken from on a boat.

Black and white lantern slide of several people playing on a large stone slab. One woman appears to be sliding down one section.

Black and white photograph of the Pikes Peak summit from the timber line.

Black and white photograph of the Pikes Peak summit at a twenty-five percent grade above the timber line.

Black and white lantern slide of nearly two dozen Chinese laborers operating a large pile driver near Mount Tai, China.

Black and white photograph of Jackson's pile driver. Four men are visible on and around the tool.

Black and white photograph of Pintada pueblo site from the southeast in New Mexico. A field is photographed with the Pintada pueblo visible in the background. Two people are visible in the right side of the frame.

Black and white photograph of the Pisa Duomo from the tower top. A man is standing in the foreground of the image looking out at the Pisa Duomo. Buildings and fields are seen in the distance.

Black and white photograph of the west doors of the Pisa Duomo. There are three doors, and the center door is larger than the two side doors.

Black and white photograph of a road lined with power lines and fences in front of a field. A barn is visible behind a line of trees. A mountain range is visible in the distance.

Black and white photograph of four men standing on makeshift wooden plank bridge over water next to a brick structure. One man is kneeling and reaching one arm into the water. A large tube is leading from a machine next to the dock into the water.

Black and white lantern slide of Robert H. Merrill standing on a runway in front of an airplane.

Black and white photograph of plane landscape toward Colorado Springs, Colorado. Taken by Robert Merrill from a moving train.

Black and white photograph of people walking and standing next to a hut with trees in the background.

Black and white photograph of two men creating plaster casts of mastodon bones, Jonio, Italy(?).

Black and white photograph of the Poe Lock, Sault Ste. Marie, Michigan. A boat is visible in the background.

Black and white photograph of the Maya Sun Calendar Cycles, published by the Eugene Dietzen Co. of Chicago and New York.

Black and white lantern slide aerial view of Pompeii. Serie Artistica No. 41257

Black and white lantern slide of the Pompeii amphitheatre looking north. Serie Artistica No. 11340

Black and white lantern slide of the Pompeii basilica looking west. Serie Artistica No. 11344