THE CANADIAN LEGACY OF THE TRANSITS

The transits of Venus had important repercussions for the development of astronomical science in Canada. William Wales, who observed the 1769 transit with the co-operation of the Hudson's Bay Company, later taught mathematics and navigation to boys at Christ's Hospital (The Bluecoat School) in London. So when the Company began to realize the need for accurate maps of their vast Canadian territory, they turned to Wales to recommend an astronomer. He had firsthand experience with the harsh conditions such a person would face, and also knew his boys' abilities. Wales recommended Philip Turnor who spent years in Canada and in 1790, at Cumberland House, trained two of our foremost map-makers, David Thompson and Peter Fidler.

The 1874 transit, although invisible here, still stirred interest and probably launched the astronomical career of Dr. Joseph Morrison. The transit of 1882 helped to build a sense of community among astronomers in Canada through work on a shared endeavour towards a common goal; it may even have served that function more broadly among Canadian intellectuals. Though Hogg (1982) associated the transit with the founding of the Royal Society of Canada, she did not claim, and there are no known records to prove, that the transit influenced the Society's establishment in that year. Still, it is not hard to imagine that Carpmael, who was one of eleven members of the Provisional Council which met in 1881 (Burpee 1932), recognized that Canadian results could be an important contribution to the new Society, as indeed they were. The transit motivated improved longitude determinations of places such as Winnipeg and Cobourg, and it was the reason for the acquisition of several good telescopes, the Toronto Observatory's 15 cm Cooke and Alan Miller's 10 cm Wray refractor. The former instrument is now at the Canada Museum of Science and Technology in Ottawa, and the latter is owned by the Victoria Centre of the RASC.

The 1882 transit attracted the attention of thousands of members of the public. Such a memorable event may have been a factor in forming a basis for public support when government astronomy in Canada began to develop in the early years of the next century. Perhaps the decision to fund the Plaskett Telescope and the Dominion Astrophysical Observatory owed more than a little to popular feeling nourished by the 1882 transit of Venus.

In a sense, the historic transits of Venus continue to pay dividends as they prompt us to look into, and perhaps preserve, some of our scientific heritage. The astronomers of the eighteenth century deserve our admiration for their perseverance, and the care, accuracy, and breadth of their observations. The activities of many amateur astronomers with telescopes in 1882 shed a bit of light on the shadowy past of our Society between 1870 and 1890. Perhaps readers will feel motivated to find out more about observers named in the newspaper accounts, and to discover what became of the equipment they used. Perhaps someone with more patience and resources than the authors will be able to say if the tendency to negative values between the observed and calculated times in Table 1 hint at an error in the theory of Venus' orbit.

CONCLUDING COMMENTS AND QUESTIONS

For everyone hoping to see the transit on 2012 June 5, there are certainly lessons to be learned from the past. Those who wish to time the contacts would be well advised to practise ahead of time with computer simulations, and to be well aware of the different stages that might be observed near internal contact, such as the halo (aureole) that surrounds the planet before second contact (internal ingress) at the commencement of the transit and before fourth contact (external egress) at the conclusion of the transit, and the black drop effect during the period of first contact (external ingress) and fourth contact (external egress). Even with such modern trappings as radio-time signals, video and digital recording, can modern observers time the contacts better than their forebears of the nineteenth or even the eighteenth centuries? Will we do better than our great-grandparents did in providing good information to the public for safe viewing? Will the media cover the event as thoroughly as they did in 1882? Will we be better at encouraging young people, especially, to devote time to see something relatively few living persons have ever seen? Who knows how many of them will be motivated to learn more about the heavens when they see the next occurrence of this rare spectacle unfolding exactly as predicted on 2012 June 5?

NOTES AND SELECTED REFERENCES

Carpmael's letter books are at Environment Canada Library, Downsview (Toronto).

The numerous unauthored newspaper sources have been listed in the body of the text, rather than here. They are all from the year 1882 unless otherwise stated.

Airy, G. B. 1880, MNRAS, 40, 381

Ball, T. and Dyck, D. 1984, The Beaver (Autumn 1984), 51

Beattie, B. 1982, JRASC 76, 109

Burpee, L. J. 1932, Fifty Years Retrospect (Ryerson Press, Toronto) p.1

Charles Carpmael 1882?/1883?, Report of the Canadian Observations of the Transit of Venus, 6th December, 1882 (Ottawa?, Queen's Printer?)

Johnson, C. et al. 1883, Trans. Roy. Soc. Canada 1, 87. This includes reports by Bain, Blake, Carpmael, Johnson, McLeod, Williamson.

Griffin-Short, R. 2003, The Beaver 83 (2), 8

Halley, E. 1715, Phil. Trans. Roy. Soc. 29, 454

Hogg, H. S. 1982, JRASC 76, 362

Holland, S. 1769, Phil. Trans. Roy. Soc. 59, 247

Hornsby, T. 1772, Phil. Trans. Roy. Soc. 61, 574

Jarrell, RA 1988, The Cold Light of Dawn (University of Toronto Press: Toronto) p. 48-50. Following p. 26 are illustrations of W. B. Jack, the Quebec Observatory, the McGill College Observatory and the Toronto Observatory.

Kennedy, J. E. 1955, JRASC 49, 151

Maor, E. 2000, June 8, 2004, Venus in Transit (Princeton University Press: Princeton NUJ) p. 91

Maskelyne, N, 1771, Trans. Amer. Phil. Soc., Appendix, 4

Morrison, J. 1873, The computation of the transits of Venus for the years 1874 and 1882, and of Mercury for the year 1878: for the earth generally and for several places in Canada, with a popular discussion of the sun's distance from the earth and an appendix showing the method of computing solar eclipses (Rowsell & Hutchison: Toronto)

Morrison, J. 1880, An elementary treatise on plane trigonometry ... designed for the use of high schools and colleges (Canada Publishing: Toronto)

Mozel, P. 1982, JRASC

Newcomb, S. 1891, Astron. Papers ... Amer. Ephem.

Schaefer, B. E. 2001, JHA 32, 325

Scientific American 1884, 50, 117

Short, J. 1762, Phil. Trans. Roy. Soc. 52, 611

Shute, M. N. (ed.) 1980, The scientific work of John Winthrop, (Arno Press: New York)

[Stone, E. J.] 1888, MNRAS 48, 201

Stone, E. J. 1892, MNRAS 52, 124

Thomson, M. M. 1978, The Beginning of the Long Dash (University of Toronto Press, Toronto)

p. 25-27. Following page 30, are photographs of the Jack Observatory in Fredericton, C. H. McLeod, the McGill Observatory, a Troughton and Simms transit instrument, J. Williamson and T.S.H. Shearman, all of whom are mentioned in this paper.

Wales, W. and Dymond, J. 1769, Phil. Trans. Roy. Soc., 59, 467

Wales, W. 1770, Phil. Trans. Roy. Soc., 60, 100

Wheatland, D. P. 1969, The Apparatus of Science at Harvard 1765-1800 (Harvard Univ. Press)

Winthrop, J. 1764a, Phil. Trans. Roy. Soc. 54, 279

Winthrop, J. 1764b, Phil. Trans. Roy. Soc. 54, 277

Wright, T. 1769, Phil. Trans. Roy. Soc. 59, 273