Theodore MacKenzie, librarian, amateur astronomer and historian of South
African astronomy, was the son of Henry MacKenzie and Marianne Duncan. He passed the matriculation examination of the University of the Cape of Good Hope in 1895 and the intermediate examination for the BA degree (equivalent to the first year of study) in 1897. He was the secretary of the Cape Astronomical Association when
it was revived around 1916, during World War I (1914-1918). The next year he
moved to Johannesburg, where he was largely responsible for the formation of
the Johannesburg Astronomical Association in February to March 1918 and was
elected its first secretary. Unfortunately his contributions to the association
were interrupted by illness in December that year. However, in 1921 he was
again a member of the association's council.
During 1922-1923 the Cape Astronomical Association and
Johannesburg Astronomical Association amalgamated to form the Astronomical
Society of South Africa (ASSA), with centres in Cape Town and Johannesburg. MacKenzie
was elected as the first secretary of ASSA, for 1922/3. However, he moved to
Grahamstown around the middle of 1923 from where he wrote articles on astronomy
for the newspaper Die Burger. During
1928/9 ASSA again established a Meteor Section (the previous one having failed
owing to a lack of observers) with MacKenzie as its director. In 1929 he was
also secretary of ASSA's Computing Section.
In 1920 MacKenzie read a paper before the Cape Astronomical
Association on 'Seventeenth century astronomy at the Cape', dealing mainly with
the work of G. Tachard*. The paper was published in the South African Quarterly and reprinted as Circular No. 7 of the association. It was followed by several more lectures
and published papers or notes on the history of astronomy in southern Africa and other astronomical topics, including the following: 'The
story of the southern constellations' (Journal
of the Astronomical Society of South Africa, 1925) 'Historic determinations
of longitude at the Cape' (South African Journal of Science, 1931), 'Early
astronomical observations in South Africa' (Monthly
Notes of the Astronomical Society of South Africa (MNASSA), 1941), 'Mason
and Dixon at the Cape' (Ibid, 1951),
and 'Historic determinations of the longitude of the Cape' (Ibid, 1952).
MacKenzie was a Fellow of the Royal Astronomical Society (FRAS). Collections of his documents, mainly historical but
also relating to the total solar eclipse of 1940, were presented to the Cory
Library for Historical Research at Rhodes University, Grahamstown.
