This series contains records from three accessions: B1994-0002, B2009-0021, and B2015-0007. The bulk of the files are from accession B1994-0002, and consists of general incoming and out-going correspondence mainly of a professional nature. It is arranged in two parts. The first part consists of files created by Helen Hogg containing correspondence and other accompanying material with individuals, institutions, clubs and associations regarding research, special projects, events, visits, excursions, travel, donations, lectures, awards and publications. For access, these have been arranged alphabetically by file title. Some of the more notable correspondence are with colleagues such as Amelia Whelau (University of Western Ontario), Steven Van Agt (Germany), Martha Liller (Harvard Observatory), Bart J. Bok (Harvard and Australia), Chu Yu-Hua (China), and there is also extensive correspondence with Harlow Shapley, director of the Harvard College Observatory and mentor to Prof. Hogg.
The second part of this series consists of miscellaneous correspondence arranged by decade. Far from being extraneous pieces, this correspondence is quite extensive and reveals much about her professional activities and on-going research. These files contain the largest volume of correspondence documenting both her and Frank Hogg's early career in the 1930s and 1940s. These files were created from loose correspondence within the records or from files, which were clearly miscellaneous.
Researchers should note that while this series does not represent the whole of the Hogg correspondence (much of which is specific to each series), it is a good representation of the scope of her interests and activities. Some of the correspondence relates directly to records in other series and researchers should bear this in mind when investigating a particular topic.