- Cayce Historical Museum, South Carolina1
- Certo2
- Charles B. Knox Co., Johnstown, New York1
- Charles B. Knox Gelatine Co., Inc1
- Charles B. Knox Gelatine Co., Inc, Johnstown, New York1
- Charles B. Knox Gelatine Co., Inc, Johnstown, New York;1
- Charles B. Knox Gelatine Co., Inc.1
- Charles B. Knox Gelatine Co., Inc., Johnstown, New York, Montreal, Canada1
- Charles Gulden, Inc.1
- Charleston Museum1
- Charleston Library Society31
- Charleston Museum4
- Charleston Museum, South Carolina2
- Charleston Southern University12
- Chester County Historical Society Archives136
- Chester County Historical Society Archives (S.C.)1,092
- Chester County Historical Society. Chester County (S.C.)204
- Chester Historical Society. Chester County (S.C.)326
- Chicago Flexible Shaft Company1
- Chicken of the Sea2