This very early Powell & Lealand microscope is modeled after the designs of Charles Gould, but also features a stirrup-shaped lever controlled mechanical stage that was invented by Cornelius Varley. Moving the lever up or down shifts the stage from side to side, an advanced feature (for the period) that enables a microscopist to follow living aquatic specimens without interrupting viewing.

The brass instrument features a cone-shaped body tube that tapers down to a screw-in achromatic objective. The compound optical system of the microscope also includes a Huygenian eyepiece and an internal field lens. For illumination, a gimbal-mounted mirror combines with an achromatic condenser above the brass stage plate. A flat tripod base and an adjustable stand that allows for multiple configurations combine to support the nineteenth century instrument. Moving the stage up and down the vertical tube stand with a rack and pinion mechanism enables coarse focus, and a large milled-head screw at the lower end of the stand pushes on the arm that supports the body for fine focusing. Swiveling stage forceps, which are included in the illustration above, are an accessory of the instrument used for holding specimens under the microscope.

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