Simple question, really. I'm not sure if I'm putting this on the right board, but I figured an engineer or two would probably know the answer. The common english abbreviation for a pound is "lb", is there any specific reason or meaning to why L and B where chosen to abbreviate this word?

Thanks for your help in advance.

The origin is in the Latin word libra, which could mean both balance scales and also a pound weight, for which the full expression was libra pondo, the second word being the origin of our pound.