REMOVE

1. Nitrate negatives
2. National parks & reserves.
3. Snow.
4. Library of Congress Prints a …
5. Genthe, Arnold
6. 1906
7. between 1903 and 1906

WHAT

1. National parks & reserves … (2)
2. Nitrate negatives (2)
3. Photographs (2)
4. negative (2)

WHO

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

WHEN

1. 1869-1942 (2)
2. 1903 (2)
3. between 1903 and 1906 (2)