Crossing the River and Marching
Now that we know when these events took place and how many men were on the expedition, it is important to compare Clark's and Bowman’s descriptions of the actions taken by the expedition.
In this case, Clark describes his men crossing a river and marching a certain distance. See if you can find where Clark mentions these actions and record what you find.
Now, look at Bowman’s account and record what he says. Does he describe similar actions taken by the troops? How is his description similar or different than Clark’s?
Now compare what you found with this example.
What did we find?
While both men mention crossing the Kaskaskia River, Clark writes that they “marched about three miles,” while Bowman records that they “marched about a league from town.” How do we know if those are similar distances?
A “mile” and a “league” are both units that measure length. Today, we are more familiar with miles than leagues.
In order to compare these two accounts and see if they agree, we will need to be able to compare the two distances in the same units. We might be able to do this by converting both distances to a common unit or we might have to investigate some other sources to learn more about both types of units. A common unit converter might look like this:
By using a unit converter, we learn that 1 nautical league = 3.45234 miles. The word “nautical” is an adjective that describes boats, sailing, and the ocean. So, a “nautical league” would be a distance that a boat would travel on the ocean. But, we are not trying to measure a “league” on the ocean. We need to find out how many leagues by land equal 1 mile. So instead, we have to find out more information about what a league is.
After further research, we discover that on land, a league is commonly defined as a 3 mile length. Some believe that the word league originated as a way to describe the distance a common man could walk in one hour.1
Now that we have the two lengths in a common unit, we can compare them:
Clark: 3 miles vs. Bowman: 1 league = 3 miles
With your new understanding of leagues, ask yourself again: How does Clark’s account compare to Bowman’s? Record your findings.
Why might Clark have recorded his distance in miles while Bowman reported his in leagues?
Sources:
1. Friedman, John Block and Kristen Mossler Figg. Trade, Travel, and Exploration in the Middle Ages: An Encyclopedia. Routledge: 2013.
Encyclopedia Britannica Online. sv. “League.” https://www.britannica.com/science/league-measurement