REFERENCES

Sir Robert Ball, Neptune's Jubilee Year, Scientific American, Supplement, Oct. 10, 1896.

Sir Robert Ball, The Story of the Heavens, chap. XV.

B. A. Gould, Report on the History of the Discovery of Neptune, Smithsonian Contributions to Knowledge, 1850.

Robert Grant, History of Physical Astronomy.

Simon Newcomb, Popular Astronomy.

Benjamin Peirce, Proceedings of the American Academy of Arts and Sciences, vol. I, pp. 57-68, 144, 285, 338-41, etc.