The device was made in 2 parts hinged, where the oakum packing was placed first and the pour-in opening was positioned at the highest point. This was difficult to pour in heated liquid lead with the ladle in the first joint, as it was the highest and VERY close to the floor above you, but the more you did it,,,,the less you spilled.
The older plumbers hated this job,, and after I grew up I saw the scars on their arms.
I didn't mind it, as I could do something the others shunned from.
That was quite an "ego" builder for a young boy.
I would never do this today!!!