466 Meteorological Observations Jo?- October 1827. 



Summary of the Weather. 

 A clear sky, 3; fine, with various modifications of clouds, 10^ ; an over- 

 cast sky witiiout rain, 10; foggy 2; rain, 3^-. — Total 31 days. 



Clouds. 

 Cirrus, Cirrocumulus. Cirrostratus. Stratus. Cumulus. Cumulostr. Nimbus. 

 22 12 31 1 22 19 18 



Scale of the prevailing Winds. 

 N. N.E. E. S.E. S. S.W. W. N.W. Days. 

 2 4^ 5| 5 4 6 2 2 31 



General Observations. — The first part of this month to the 8th was fine 

 and dry, and the latter part humid, wet, and windy. On the 8th, 9th, 1 0th, 

 and 28th, nearly 3^ inches of rain fell here, when chronic rheumatism 

 and colds were prevalent complaints in this town and neighbourhood. A 

 northerly wind on the 13th lessened the temperature of the atmosphere 

 considerably, and made it a winter-like day ; but a South-west wind with 

 rain on the following day increased it again, and it kept up warm till the 

 27th, afterwards it was cold to the close of the month, with hoar-frost in 

 the mornings. 



On the evening of the 17th a faint appearance of an aurora borealis was 

 observed here; and one at Manchester on the evening of the 6th in the 

 moon-light. 



It is remarkable that in the morning of the 18th, linear, ramified, and 

 converging plumose cirri appeared beneath beds of cirrocumulus in round 

 flocks ; and these modifications were beautifully tinged with prismatic co- 

 lours, both within and two or three degrees without a solar halo, whose 

 horizontal radii were respectively 22J degrees. In the afternoon of the 

 19th, a beautiful rainbow appeared from a quarter before five till five o'clock. 

 The diameter of the interior bow to the outside of the colours measured 

 84° 5', and of the exterior, 101° 10', and their distance from each other 

 was 8° 17'- The colours of the interior bow downward were red, yellow, 

 green, and faint blue, beneath which four narrow parallel bows appeared 

 of a deep red, with collateral modifications of colours, which bows were 

 formed by successive reflections from the interior bow. The breadth of the 

 exterior bow was nearly two degrees, notwithstanding the nimbus, in which 

 it appeared was only of a turbid hue, and its colours were reversed from 

 the order of those in the exterior, which showed that the former was 

 formed by reflection from the latter. The sun was in the horizon, and 

 within a few minutes of setting when the bows disappeared. 



The mercury in the barometer on the 25th and 28th slowly rose whilst 

 it rained. This is an anomaly in meteorology in this latitude, as it seldom 

 happens. On the 2.5tli, its rising was occasioned by a simultaneous dry 

 wind setting in above the rain from the N.W., as discovered by the motion 

 oi cirrus from that point nearly when the nimbus began to disperse, thereby 

 closely uniting the particles of th(^ air, so as to increase the weight of the 

 atmospheric column in our zenith ; and on the 28th its rising was also oc- 

 casioned by a wind from the N.E, blowing over a light current from the 

 S.W. till it succeeded it at noon. 



The mean temperature of the external air this month is only 2}j degrees 

 higher than the mean of October for the last eleven years. 



The temperature of spring water did not arrive at its maximum till the 

 26th, consequently the earth had but just attained its greatest heat for this 

 year ; and it decreased half a degree by the end of the month. 



The 



