QUESTION:
What test did you do to see what it would take to crush the Sojourner?

ANSWER:
Sojourner will not be subjected to a crush environment, and therefore 
we did not do any test to simulate that sort of thing. However, we did
perform a battery of standard spacecraft mechanical tests to simulate
other environments:

Acoustic test - The noise during liftoff is typically so loud that it 
can severely rattle the spacecraft and Rover. Therefore, we performed 
an acoustic test on certain Rover components (like the solar panel) by
suspending them in a large acoustic chamber. Large speakers were used 
to generate the noise that simulates the launch.

Vibration test - This is a test that simulates the vibration that is 
passed through the launch vehical and spacecraft to Sojourner. We 
strapped the Rover onto a hydraulically controlled "shake table" and 
vibrated it a different frequencies.

Acceleration/Deceleration - The landing on Mars will require that the 
Rover survive a rapid deceleration of up to 40 g's (which is a lot 
more than any fighter pilot ever pulled in a plane). This test involved 
setting the Rover on the end of an arm, then rotating the arm at very 
high speeds.

Shock Test - Another test done was a shock test with small expolsive
charges. This simulates the shutter caused by the small explosive 
charges on the spacecraft which are used to release mechanisms and cut
cables.

ANSWER from Guy Beutelschies on April 29, 1997:
We tested the lander and Sojourner for over a year and a half before we
launched it.  We ran hundreds of individual tests making sure each part
worked as expected.