Louisiana Purchase

Cost of the Louisiana Purchase: $15 million
Cost per acre: 3 cents¹

Land area added to United States by the Louisiana Purchase: 828,000 square miles²

Approximate ratio of the size of the Louisiana Purchase to the size of United States prior to the Louisiana Purchase: 1:1

Haitian Revolution

1789 rank of Saint-Domingue (Haiti) among the world's most valuable colonies: 1³
Today's rank of Haiti, among the poorest countries in the Western Hemisphere: 1⁴

Number of soldiers in Napoleon's army killed in Saint-Domingue (Haiti): 27,000
Number of soldiers in Napoleon's army killed at Waterloo: 25,000

Lewis and Clark Expedition

Number of rifles carried by Lewis and Clark's Corps of Discovery on their journey to the Pacific: 15
Number of blankets: 15
Number of knives: 288
Number of brass thimbles: 288
Number of Dr. Rush's patented "Rush's Thunderclappers" pills: 50 dozen
Pounds of soap: 12
Number of copies of Linnaeus, the Latin classification of plants: 1
Number of maps: 1⁵