A rotating barrel butter churn patent model is the subject of this albumen CDV, photographed by Ruggles & Hentz of 1823 Washington Street, Roxbury District, Boston. The deliberate, object-focused composition suggests the image was made expressly to document an invention, a practice common among patent applicants and inventors in the latter half of the nineteenth century.

The barrel is horizontal, mounted on a jointed wooden cradle frame with crossed diagonal bracing at the front and a rectangular base structure resting on a draped table. A metal funnel is fitted into the front face of the barrel at center, feeding into a mechanical fitting or valve at its base, with what appears to be a small hinged access door visible at the lower front of the frame.

Product and patent documentation photographs of this type are uncommon survivals, particularly when attributed to a specific studio. Ruggles & Hentz operated at the Roxbury District address after the street was renumbered, placing this card in the post-annexation Boston period following Roxbury's consolidation with the city in 1868.

The reverse bears the printed imprint "Ruggles & Hentz, Photographers, 1823 Washington St., (formerly 69,) Roxbury District, Boston" and the notation "Negatives preserved."