This fonds consists of research materials collected by Professor Ross Irwin for his book on Mariposa Township, Victoria County. Material added August 1992 includes a copy of Mariposa: The Banner Township and a series of 8 scrapbooks created by Mrs. Alex McIntyre of Oakwood, Ontario and donated via Professor Irwin. Additions of 1994 include slides of Lindsay, Ontario and other scenes in Victoria County taken in approximately the 1960s. Additions of 2002 include 2 notebooks of Robert Irwin, Cambray. Additions of 2010 include studio portraits of ancestral family members. Additions of 2012 include items related to the history of the Wakelin family and a scribbler with house-building notes.

Collection consists of an inventory of land locations for early settlers and inhabitants of Ops Township from the initial survey of the township in 1825 to 1872. It includes census information and assessments of households, various voter's lists, many Ops Township documents and one map for the 1839 Assessment Roll. The collection also includes a variety of cookbooks, recipes, food preparation manuals for specific cooking devices, and research notes.

The fonds includes photocopies of the following items: Township Patent Book, 1820-1872, including the names of the grantees, lot purchased and dates as well as township/municipal election returns, and oaths of office for 1850. It also includes the correspondence of John Reid, township road surveyor, with elected officials and citizens, including maps, drawings etc.; township business papers, including receipts, taxation abatements, and school business; and Statute Labour lists and returns for the year 1850.

This fonds consists of research papers and notes pertaining to the publication of the Peterborough Historical Atlas in 1975 and the subsequent activities of the Peterborough Atlas Foundation.

This addition to the fonds consists of surveyor's plans for lots mainly in Ashburnham and Peterborough drawn by surveyor Alfred Cameron.

The fonds consists of personal and business correspondence and papers for several members of the Cameron family who lived in Peterborough, Upper Canada. It includes correspondence between Charles Cameron and his wife Sophia (Barron) Cameron, 1852-1881; business correspondence, invoices, receipts, and accounts for McKeller and Cameron Dry Goods Merchants, 1861-1870; Charles Cameron business correspondence, invoices, receipts and cancelled cheques from his years as an insurance agent, 1871-1903; Alfred Cameron personal and business correspondence, 1886-1908; Alfred Cameron survey reports for various townships, towns and villages in Peterborough County, the United Counties of Northumberland and Durham, Simcoe County, Nippissing District, and Cochrane District, 1894-1931; Alfred Cameron insurance policies; and a Chas. E. Goad fire insurance plan of the town of Peterborough and the village of Ashburnham, 1882, revised 1889.