Oakum
Oakum can be used to seal cast iron pipe drains. After setting the pipes together, workers pack oakum into the joints, then pour molten lead into the joint to create a permanent seal. The oakum swells and seals the joint, the "tar" in the oakum prevents rot, and the lead keeps the joint physically tight.
Today, modern methods, such as rubber seals (for example, gaskets or o-rings) are more common.
List of tar pits
This is a list of notable tar pits throughout the world. Tar pits, which are often covered with dust and leaves can trap animals that step into them. Over time, the skeletons of such animals become preserved as fossils. Some of the largest deposits of fossils exist within tar pits.