One of two types of hand grenades developed during the early years of the Civil War. Unlike the more common Ketchum grenade, this type was developed by W.W. Hanes in early 1862. He names his patented invention the "Excelsior" grenade. This device is a small cast-iron shell with percussion nipples, each requiring attachment of a percussion cap before throwing the grenade. It would only take one cap to trigger the explosion, and soldiers trying to use Hanes's grenade found out the hard way that it was too easy to accidentally set off one of the percussions caps. This resulted in the Excelsior grenades never being used in battle or, at least, there has not been a recorded battlefield find of one. These grenades are exceedingly rare. This example is a variant roughly cast in two sections with 10 brass nipples inserted and two fill holes.

Text and photo © "an eBay seller".

The two cover halves on the photos below came from an auction on the web.
I have not found any info so far on the name "Pelican", but these covers are the same as the exelsior should have.