"If this [glacial] theory be correct, and the facility with which it explains so many phenomena which have hitherto been deemed inexplicable, induces me to believe that it is; then it must follow that there has been . . . a fall of temperature far below that which prevails in our days” (Louis Agassiz, 1837, p.377).

In the 1840s geologists faced the possibility that the Earth was once very cold, with Europe covered in glaciers. Evidence supported both accepting and rejecting this idea. This case study allows you ro address the evidence of the time and decide for yourself. In the process, you should learn a bit about Earth's history, how scientists interpret evidence, and also how science is shaped by personality, cultural context and lively debate.

To experience the life of a 19th-century geologist well, you need to travel and visit significant sites around Europe. Here you will do this using Google Earth ( the "Tour") -- see below for set-up. You will also read about how those observations were interpreted through original publications from the 1800s (the "Episodes"). This background will allow you to address the provocative theory first presented by Louis Agassiz and William Buckland at the Geological Society of London in 1840: that thick ice sheets once covered the land!

Two tracks are available:

1. Self-Guided Option -- Follow the story as a neutral observer, and document your study and views as indicated by your instructor. OR
2. Debate Simulation -- Assume the role of one of the participants and engage in a live debate with your peers at the Geological Soceity of London in 1842.

SET-UP for Touring:

1. Install GoogleEarth on your computer.

2. You may also download the program-data file that contains the tour and save it on your computer for future use.

3. When using Google Earth:

(a) To ensure you see the text associated with each PlaceMark double-click the listing of locations in the left-hand "Places" menu rather than clicking on the map icons

(b) To close the Placemark window click "x" in the top right; to re-open the window single-click the Placemark listing in the "Places" listing

(c) To return to a European-wide view at any time, double-click the file header in the "Places" listing (i.e. "Glacial Theory . . . ")

With set-up completed,

Begin self-guided study   OR   Proceed to Debate Simulation Profile.