REMOVE

1. Timeline
2. Historical
3. Europe
4. Mexico

WHAT

1. Data Visualization (6)
2. Historical Atlas (6)

WHERE

1. Canada (6)
2. United States (6)

WHO

1. Boynton, G. W. (6)
2. Holgate, Jerome B., 1812- … (6)
3. J.B. Holgate (6)

WHEN

1. 1842 (6)