Avery 2 lb Scale.

This single beam counter scale utilizes the Roberval system. Created by Gilles Roberval in 1699, it is a construction that keeps the pans level as they move up and down. More importantly, it prevents the pans from tilting as they move up and down, and this is the principle that ensures that the position of the weights on the pans has no effect on the balance. The scale is embossed "W & T Ltd, To Weigh 2 lb". The cast iron scale supports solid brass load and weight pans and brass balance indicator. England, Ca. 1920.

Avery 2 lb Scale; (No. C638). Dimensions: 12.5"W x 3.5"D x 7.5"H; load pan: 6.75" x 5.75"; weight pan: 4.5" diameter. Shipping: $25.