The organ in St. Mark's Church was built ca. 1905 by the Votteler-Hettche Company, Cleveland, Ohio, for the New Haven Church of Christ, New Haven, Indiana. With the assistance of the Organ Clearing House, the organ was purchased by St. Mark's Church in 1977 and moved to the Aldenville, Massachusetts workshop of the Stuart Organ Company for rebuilding. The revised tonal scheme, prepared by Richard S. Hedgebeth, head of the firm, in consultation with James Armstrong, organist of the church, reflects classical principles of organ design. The organ, now encompassing 640 pipes distributed among 10 stops, retains the original casework of oak, restored and refinished to harmonize with the woodwork of the church's new building.