moon.

[4] _On early meteorology in the United States see the report of Joseph
Henry in Report of the Commissioner of Patents, Agriculture, for the
Year 1855_, 1856, p. 357ff.; also, _Army Meteorological Register for
Twelve Years, 1843-1854_, 1855, introduction.

[5] J. D. Forbes, "Report upon the Recent Progress and Present State of
Meteorology," _Report of the First and Second Meetings of the British
Association for the Advancement of Science, 1831 and 1832_, 1833, pp.
196-197.

[6] On the instruments used at Mannheim see Gerland and Traumueller, _op.
cit._ footnote 1, p. 349ff. The Princeton physicist Arnold Guyot
prepared a set of instructions for observers that was published in
_Tenth Annual Report ... of the Smithsonian Institution_, 1856, p.
215ff. It appears from the _Annual Report of the British Association for
the Advance of Science_ in the 1830's that the instruments used in
England were nearly the same as those later adopted by the Smithsonian,
although British observatories were beginning to experiment with the
self-registering anemometer at that time. A typical set of the
Smithsonian instruments is shown in figure 1.

[7] H. Alan Lloyd, "Horology and Meteorology," _Journal Suisse
d'Horlogerie_, November-December, 1953, nos. 11, 12, p. 372, fig. 1.

[8] R. T. Gunther, _Early Science in Oxford_, vol. 6, _The Life and Work
of Robert Hooke_, pt. 1, Oxford, 1930, p. 196. In 1670, Hooke's proposed
clock was referred to as "such a one, as Dr. Wren had formerly
contrived" (Gunther, p. 365).

[9] William Derham, _Philosophical Experiments and Observations of ...
Dr. Robert Hooke_, London, 1726, pp. 41-42 (reprinted in Gunther, _op.
cit._ footnote 8, vol. 7, pp. 519-520). This description, dated December
5, 1678, predates the Royal Society's request for a description
(Gunther, _op. cit._ footnote 8, p. 656) by four months, but the Society
no longer has any description of the clock. As to the actual completion
of the clock, the president of the Society visited "Mr. Hooke's turret"
to see it in January of 1678/79 but it was not reported "ready to be
shown" until the following May (Gunther, pp. 506, 518).

[10] Wren's clock and its wind vane and anemometer, thermometer,
barometer, and rain gauge are described by T. Sprat, _The History of the
Royal Society..._, London, 1667, pp. 312-313. On the balance-barometer,
see also footnote 28, below, and figure 4.

[11] Since the above was written, additional informatio