Candid photograph of Seymour and Gibson, who is approximately 70 years old, looking at a photograph of Macaulay.

Candid photograph of Kouwenhoven lecturing behind a desk with his fingers pointed.

Candid photograph of Kouwenhoven lecturing behind a desk with his fingers pointed.

Candid photograph of Kouwenhoven lecturing behind a desk with his arms outspread.

Candid photograph of Kouwenhoven lecturing behind a desk with his arms outspread.

Candid photograph of Kouwenhoven at 82 years old, attending the Edison Electric Institute Convention in Miami with his wife, Abigail Baxter Remsen.

Candid photograph of Kouwenhoven at 82 years old, attending the Edison Electric Institute Convention in Miami with his wife, Abigail Baxter Remsen.