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A new stereographic protractor1

Published online by Cambridge University Press:  14 March 2018

G. F. Herbert Smith*
Affiliation:
Mineral Department of the British Museum

Extract

In the stereographic projection (fig. 1) ABA'B" is the primitive circle, having the same radius a as the corresponding sphere ; ATA'T" is the circle representing a great circle on the sphere inclined at an angle θ to the plane of the projection ; O and C are the centres of the primitive circle and the circle ATA'T' respectively. CO are joined and projected both ways to meet the circles as shown.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1913

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Footnotes

1

Communicated by permission of the Trustees of the British Museum.

References

page 46 note 2 Cf. Hutchinson, A., 'On a protractor for use in constructing stereographic and gnomonic projections of the sphere.' Min. Mag., 1908, vol. xv, pp. 93112 CrossRefGoogle Scholar.

page 46 note 3 Penfield, S. L., Amer. Journ. Sci., 1902, ser. 4, vol. xiv, p. 251 Google Scholar.

page 47 note 1 A. Hutchinson, loc. cit., p. 94.

page 47 note 2 Fedorov, E. S., Zeita. Kryst. Min., 1893, vol. xxi, p. 622 Google Scholar.

page 47 note 3 Fedorov, E. S., Zeits. Kryst. Min., 1893, vol. xxi, p. 618 Google Scholar. G. Wulff, ibid., p. 258. Vide also Penfield, S. L., Amer. Journ. Sci., 1901, ser. 4, vol. xi, p. 138 Google Scholar.

page 47 note 4 Fedorov, E. S., Zeits. Kryst. Min., 1902, vol. xxxvii, p. 142 Google Scholar.

page 48 note 1 Bernoulli, J., ‘Sur la force et la courbure des lames élastiques.’ Mém. Acad. Berlin, 1766 Google Scholar.