Historical information
The first spring balance in Britain was made around 1770 by Richard Salter of Bilston, near Wolverhampton. He and his nephews John & George, founded the firm of George Salter & Co., still notable makers of scales and balances, who in 1838 patented the spring balance. They also applied the same spring balance principle to steam locomotive safety valves, replacing the earlier deadweight valves.
https://en.wikipedia.org/wiki/Spring_scale
Today, spring scales are very popular with recreational fishers.
Significance
The ability to weigh things reasonably accurately with a small inexpensive apparatus allowed for the exact weight of items to be ascertained. However, it was not accurate enough to weigh small amounts in ounces or grams.
Physical description
Scale. Has ring for hanging, spring and hook device for weighing. Measures in lbs.
Inscriptions & markings
Scale of pounds weight.