Henry Pilcher's Sons
1886

The School Chapel was built 1881-1886. The earlier Pilcher (1872) would have been installed in another building, probably part of the main building. From the 'About' web page:
"Built in 1881 and completed in 1888, St. Mary's Chapel was built to accompany St. Mary's School, traditional all-girls charm school where they centered triangular teachings around Education, Church, and Home. Often attended by wealthier Chicagoan daughters "for higher learning," its most local historical highlight is that it is said to be the charm school of American President Gerald Ford's late mother, Dorothy Ayer Gardner Ford."

Further history on the school:
"A history of this school should be prefaced by a sketch of another institution of learning, which stood on the same ground and of which St. Mary's was the outgrowth. In February, 1859, a charter was procured from the Legislature for the establishment of an institution of learning called the Ewing Female University of Knoxville. It was named in honor of an old resident of the city. A good, substantial building was erected, and the school was opened and was continued until 1867, when it was closed and the scheme abandoned.

Dr. Charles W. Leffingwell was called to take charge of the new institution as Rector, and it may be truly said became the founder of St. Mary's School. It was opened April 12, 1868, after improving, rearranging and refitting the building. "Within four years the school outgrew its accommodations, and received from the late James Knox $10,000 for the purpose of enlargement. In addition to this about $50,000 was expended in building and equipping the school. "

As of 2023, the organ was intact but in need of adjustments.

https://www.stmaryschapelandevents.com/gallery?lightbox=dataItem-ldpjsud0

Web site says still playable in May, 2023

On-line update from David Kinyon -- I have never seen this instrument. Its condition is unknown. The chapel sits alone in the middle of a field, the college long since razed/burned in the late 19thc. It is privately owned now and the current owners do not allow visitors on site except on very special occasions. There is no electricity in the chapel to date. It is only used for private functions and funerals once or maybe twice a year. As of 1982, it is believed the organ was playable and totally unaltered, although the elements and lack of use are bound to have taken their toll by now.

Was St. Mary's Episcopal College chapel.