This telescope was built in 1852 by Henry Fitz, considered by many to be the first important American telescope maker. The objective lens is 12 inches (30 cm) in diameter, with focal ratio f/16.5. The 12-in telescope is regularly used for teaching the Department's introductory astronomy subjects.
Its original owner was Jacob Campbell, a banker living in Brooklyn Heights, New York, and it was one of the largest privately-owned telescopes in the world. Mr. Campbell built a garden observatory in 1854, where he used the telescope until his death in 1864. The house, observatory and telescope were purchased the next year by Stephen Van Cullen-White, a lawyer. Disappointed with the views produced by the telescope, in 1867 he contracted Alvan Clark & Sons, the premier American telescope makers of the later nineteenth century, to refigure the objective lens. Mr. White became a very successful broker, banker, and U.S. representative, and he made the telescope available to local amateur astronomers and school classes. One teacher taking advantage of Mr. White's generosity was Miss Sarah Whiting of the Brooklyn Heights Seminary who, in 1879, would come to Wellesley College as a physics professor.
By 1898, Mr. White had suffered severe financial losses in the markets, forcing him to put his home and observatory up for sale. Professor Whiting learned that the telescope she had used and loved so many years ago was for sale, and suggested it as the centerpiece of an observatory for the College. Mrs. Sarah Whitin, a trustee of the College, enthusiastically agreed to finance the project. Construction of the observatory began in 1899 and was completed the following year.
The dome was built by Warner & Swasey of Cleveland, Ohio, and shortly after its installation the builder estimated that its weight was 15,100 pounds. The telescope tracked using a weight-driven clock drive until 1954, when it was replaced with an electric motor. The stone pier and equatorial mounting are the originals provided by Fitz, although the mounting has been modified several times. In the mid-1980s John H. Richardson of Needham, a retired MIT machinist and craftsman, refurbished the 12-in telescope (and also the 6-in telescope). Photos of the restorations can be seen in the Image Gallery.
Since 1988 the telescope has been used with the aid of Advanced Technology Instruments “CAT” electronic setting circles. John and Natalie Richardson donated the $1350 purchase cost as well as “the design and fabrication of all associated mechanisms and hardware necessary to couple the unit to the telescope.”