On May 17, 1870, the quarterly conference of the church authorized use of a reed organ in worship. Dr. William L. Heiskell, a local dentist, organized a choir, which he directed for more than twenty years. Heiskell was a member of the committee that selected the first pipe organ for the new church. Wm. H. Clarke & Co. of Indianapolis supplied this instrument, which was inaugurated on Monday evening, June 12, 1876, with an "opening exhibition." The program featured Clarke as organist and the "Harmonic Society" and included selections from Sir Michael Costa's Naaman. The cost of the organ was $10,500. A letter in the Indiana Historical Society Library, dated February 23, 1876, to M.H. Haley of Crawfordsville, Indiana, from Wm. H. Clarke & Co. states that the factory was beginning work on this organ at this time, as it had just finished and shipped an organ to Lima, Ohio. The builder wrote to H.H. Wiser & Co., of Chicago, Illinois, March 21, 1876, inquiring about having two carvings made for this facade, the angels seen today, asking for a price in walnut and for a softer wood. A letter of April 25, 1876, from Wm. H. Clarke & Co. to Reverend C.D. Battiste [?] of Gallipolis, Ohio, notes that the Roberts Park organ was to be the "largest in the west outside of Chicago," with 60 stops [sic] and 2,606 pipes. Research by Michael Friesen notes the organ was shipped in May 1876. The black walnut case was twentythree feet wide and fifteen feet deep. Manual compass was sixty-one notes (CC-c4); pedal compass (flat pedalboard) was thirty notes (CC- £').
-- 2007 OHS Atlas

Updated through online information from T. Daniel Hancock. -- William Horatio Clarke writes in 1877, "A large Three-Manual Organ, containing 60 Draw-Stops, including 10 Pedal Registers, and is supplied with wind by Hydraulic power." This is followed by a testimonal [page (1)] from the church Pastor, Trustee Chair, and Organ Committee Chair.

Replaced by E. M. Skinner Opus 234 (1915), retaining the case.