A native of East Middlebury, Vermont, Partridge was educated in Middlebury, attended Middlebury College, and graduated from Amherst College (1882) and Columbia Law School (1884). Proctor practiced law in Rutland before becoming active in the Vermont Marble Company and associated politically with the company's owners, the Redfield Proctor family. Partridge advanced up Vermont Marble's ranks beginning in the mid-1880s, and served successively as Treasurer, Vice President, President, and Chairman of the Board. In addition, he was affiliated with other Proctor businesses, including the Proctor Trust Company and the Clarendon and Pittsford Railroad.