This early grenade was made in three sizes, 1pound ,3pound and 5pound.
The body was made of cast iron and was stabilized by a wooden tail with paper fins.
When thrown, the tail would make sure that the grenade landed on its percussion fuze.

1lb / 3lb / 5lb :

Total length : 31 /33 / ?mm
Body length : 90/112 / ?mm
Tail length : 23mm
Diameter plunger : 50mm

Photo right © Cory (1lb&3lb).

5lb :