In the following activity you will use your Cram Horizon Ring globe
to learn more about one of the most significant events in the shaping of
the modern world.
Place the globe ball of your Cram globe in its cradle so that the
equator is even with the top of the mounting ring. Look at the mileage
scale on ring. How many miles is it around the earth? (1.)
Now look at the outer scale on the ring. The scale is divided into
one-hour segments. In the upper right-hand corner of each one-hour
segment you will find a number that shows degrees. The number at the end
of the first one-hour segment after the red line is "15". Starting at
the red line and moving your finger to the right you will find that the
degrees increase as you move around the ring. Continue moving your
finger along the mounting until you end up back at the red line. How
many degrees are in the complete circle? 2. ______________________
If there are 25,000 miles in 360 degrees around the earth, how many
miles would there be in one degree? Round off your answer. (3.)
________________ Since the earth is divided into 360 degrees of
longitude, would it be accurate to say that, at the equator, one degree
of longitude equals 69 miles?(4.)
When Christopher Columbus landed in North America on October 12,
1492, he thought that he was in Asia. (Note: All the dates used in this
activity are the ones used in Spain during the time of Columbus. To
bring them in line with our modern calendar, advance the dates nine
days.) By using the information above and your globe, you will gain a
better understanding of how Columbus made this mistake and why he
believed that he had been successful in finding a shorter route to the
riches of the East.
Columbus, like many others of his time, thought that there were only
56 miles in a degree of longitude at the equator. If he had been
correct, and one degree of longitude at the equator really had equaled
56 miles, what would have been the distance around the earth? (5.)
_______ _____________ This distance of approximately 20,000 miles is
what Columbus believed to be the distance around the earth. To get an
idea of how big this is, start at the red line and move your finger
around the mounting ring to the 20,000 mile mark.
This mistake, along with Columbus's over estimation of the land
distance across the land mass of Eurasia, led him to believe that Japan
was only 3000 miles west of Portugal and the East Indies were only
Now, lets trace his voyage and see just why he was so convinced that
he was right when he landed in the New World. On your globe place a
small "X" on the European coast at 37N/7W. In what country is this
location? (6.) _____________ To the right of this location write the
date "8/3/1492". This is the date that Columbus, along with a crew of 90
men, set sail in three small caravels (a type of ship) on
a voyage that forever altered the course of history.
From the "X", draw a line in a southwesterly direction to a group of
islands at 28N/16W. What are these islands called? (7.)
___________________________ To the left of these islands write the date
9/9/1492. This is the date that Columbus and his men last saw land on
the outbound leg of their voyage.
From the Canary Islands, extend your line westward to another group
of islands at 23N/75W. Next to this location write the date 10/12/1492.
This was the date land was first sighted after 33 days at sea. These
islands are part of what island group?(8) _____________________________
What two large islands are located just south of this location? (9)
_________________________ What sea is located south of these islands?
Study the route that you have traced on the globe. Can you find a
reason that might have caused Columbus to first sail south before
turning west to seek Asia? Why do you think he followed this route?
What is the name of the current that Columbus used to help him sail west
from the Canary Islands? (12.) _______________________________________
Was it a warm current or a cold current? (13.)
Use the mounting ring to measure the distance between the Canary
Islands and the West Indies. How far is it?
(14.)__________________________________________________ Is this about
the distance where Columbus had predicted that he would find the East
Indies? (15.) ____________ If it took 33 days for Columbus to sail
between these two locations, what was the average distance covered each
day? (16.) ___________________________________________________
Columbus was probably the finest sailor of his time, and he
understood well the patterns of winds and currents in the North Atlantic
Ocean. On January 16, 1493, he departed from the northeastern shore of
the island of Hispaniola near 19N/68W for the return trip to Spain. Draw
a route on your globe that you think he may have followed. Justify your
choice. (17.) _________
Though he was mistaken about his location when he landed in the
Americas, Columbus's route and sailing techniques for getting his ships
there and back could not have been better planned and executed. Sailing
vessels traveling between Western Europe and North America were to use
Columbus's route for the next four hundred years. Even with today's
detailed geographical knowledge and sophisticated navigational aids, a
modern sailor can do no better.