Why Are We So Obsessed with Time Capsules?

If you think about it, burying a bunch of random stuff in the ground isn't the most logical practice. But for centuries, people have created time capsules for future generations to find. Today Will and Mango dig in, literally, to this strange phenomenon. What counts as a time capsule? Are there limits to what can be preserved? What are the most surprising (and disappointing) objects ever hidden…