Taken from the Stanton Industries web site:

Analytical Balances
Analytical balances are high-precision scales with a capacity of typically 200 grams and a resolution of 0.1 milligram. Before the advent of single pan balances this meant classical twin-pan design with or without a variety of auxiliary devices such as damping, rider mechanisms, weight loading, optical projection, and others to speed up weighing and increase resolution. The pictures below give an overview of Stanton's output from this category.

Model A42, analytical balance with 200 g capacity and 0.1 mg optical resolution. By the end of the 1950's, grey painted cases had displaced the mahogany finish. Basically a modern verion of the AD2.

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