XXVII, 
MISCELLANEOUS NOTES AND OBSERVATIONS. 
Bead at Watford, 1 9th April, 1887. 
Meteorology. 
Fog-Bows at Odsey .—A white Fog-how was observed here on 
16th February, 1887, between half-past nine and ten o’clock in the 
morning. With a low sun, and a broken fog drifting with the 
wind, a bow was thrown from time to time on one mass of fog by 
the sun-light passing through another. It was perfectly white, 
hut never very distinct. There was a sharp frost at the time. 
I have also recorded a fog-bow, seen here on 23rd December, 
1879, between eleven and twelve o’clock in the morning, in a letter 
in the ‘Meteorological Magazine’ for January, 1880 (vol. xiv, p. 192), 
giving the following particulars: “A low white fog of varying 
density was driving before a moderate E.S.E. wind, with sun-light 
occasionally gleaming through it. In these lighter intervals a dis¬ 
tinct white bow appeared on the fog in the N.N.W., at a short 
distance from the observer. This bow varied in clearness, generally 
in proportion to the amount of sun-light, and in its various parts 
according to the definiteness of the fog on which it was projected. 
It was perfectly white, but similar in other respects to a rain-bow. 
The weather was frosty.” 
This phenomenon is probably not uncommon, although, as the 
how is white and rarely well-defined, it is not often recorded. It 
may always be looked for in the winter, when the early morning is 
frosty and foggy, and, after the sun has attained some height in the 
heavens, the fog is gradually broken up by wind. A number of 
observations and notes on this subject are collected by Mr. G. J. 
Symons, F.B.S., in a paper, “ On a White Fain or Fog-bow,” pub¬ 
lished in the ‘ Quarterly Journal of the Meteorological Society’ for 
October, 1875, in which (at p. 443) he cites the following explana¬ 
tion from ‘A Treatise on Meteorology,’ by Elias Loomis, LL.D. 
(New York, 1868), p. 214: “If the rain-drops be less than - 7 Vth 
of an inch in diameter, the primary bow will be wider than 2°, the 
breadth of the bow depending simply upon the size of the drops. 
But as the breadth of the bow increases, the colours are spread over 
a greater surface, and consequently they are less vivid and distinct. 
When the diameter of the drops is xzw of an inch, which is the 
average diameter of particles of fog, the bow becomes a very faint 
arch 4° or 5° in breadth, with only a slight rosy tint upon the out¬ 
side. Such a bow is actually observed when the sun shines upon a 
dense fog.” 
[. Postscript , Sept., 1887. In the ‘Meteorological Magazine’ for 
August, 1887 (vol. xxii, p. 108), the Editor has reprinted from the 
‘ Beport of the Marlborough College Nat. Hist. Soc.’ for the year 
ending Christmas, 1886, notes of two white fog-bows seen, the 
