REMOVE

1. Portrait photographs
2. Photographs
3. Nitrate negatives
4. negative
5. Genthe, Arnold
6. between 1923 and 1929

WHAT

1. Horses. (1)
2. Nitrate negatives (1)
3. Portrait photographs (1)

WHO

1. Genthe, Arnold (1)
2. Library of Congress Print … (1)

WHEN

1. 1869-1942 (1)
2. 1923 (1)
3. 1929 (1)
4. between 1923 and 1929 (1)