The records comprise diaries, minutes, correspondence, memoranda, scrapbooks, registers, press-clippings, legal and ecclesiastical documents, photographs, printed items and plans. These records were transferred to the C.P.S.A. record Library in July 1972 from Darrah Hous, just prior to its demolition to make way for a new block of offices and flats, which is to be built on the same site, adjacent to the Cathedral.
From the records one obtains a clear picture of the beginning of the Anglican church in Johannesburg, of its work and growth and importance in the life of the community. The records contain much on the buying and selling of stands, on the raising and spending of money and on the relationship of St. Mary's with first of all, the Diocese of Pretoria and from 1922 with the Diocese of Johannesburg. There is much on the building, repair and ornamentation of the various St. Mary's churches, the services held, the elections and work of churchwardens and on activities closely linked with the church such as the choir, Church Men's society and the Dean's Shelter for the aged, unemployed and homeless. Closely associated with St. Mary's were might be described as her 'daughter' churches, St. Alban's, St. Cyprian's and St. Saviour's and the records contain information on their beginnings and on the missionary and educational work done at St. Cyprian's for the Bantu and at St. Alban's for the coloured people.
The records also throw light on the history of St. John's College and on the work done at St. margaret's Mission House by the sisters of East Grimstead. Side by side with the records of the church itself go the records of its commercial buildings, first St. Mary's buildings in Eloff Street (built on the site of the first St. Mary's church) and later Darragh House in Plein Street (built on the site of the second St. Mary's church), both of which produced revenue from the rents of offices, flats and shops. There is a great deal in the records on the leasing and upkeep of these buildings.
The records of St. Mary's Church are of interest not only to the church historian but also to researchers enquiring into the history of education, social services and property development in Johannesburg.