Manhole covers are solid — to keep sewer odor from ... the sand holding its shape even when flipped upside-down. As this is done, across the factory floor, the iron that will go inside is ...

Manhole covers are designed to stay in place, with their round shape preventing them from falling in. But they can become ...

The force of the explosion was so large it blew the steel manhole cover up over the house on Cross Street and then back down where it pierced the roof. Several windows were shattered by the impact ...