544 Singular Rainbow. 
reduced to 7°.* Of course, the cold produced in this manner 
was speedily dissipated after the appearance of the sun above 
the horizon; and the ensuing day proving equally fine with 
those that had preceded, I was enabled to observe the utmost 
intensity of the sun’s rays, which, at 1 p.m., had raised to the 
height of 105° the same thermometer which at 6 a. M. was 2° 
below the freexing point; so that in seven hours the vegetation 
of that spot experienced a range of temperature equalling 75°. 
At the time of the above observation, the temperature of the 
air was 63°, indicating the force of solar radiation to have 
been 42°. 
The first week in April presented a striking contrast to the 
last week in March. On the 2d of that month, being only 
four days after the temperature of the air had risen to 69°, 
the thermometer was never higher than 34°; and snow and 
sleet together, accompanied by a keen wind from the north- 
east, continued falling without interruption the whole day. 
This was followed by several nights of very severe frost, inso- 
much that, in one instance, the morning of the 5th, the ther- 
mometer, exactly at sunrise, stood as low as 25°; whilst 
another on the grass, placed as on the occasion before men- 
tioned, was depressed to 20°. Soon after this, however, the 
weather again became seasonable. 
I have only to add, in concluding this subject, that the 
whole of the above observations were made at Swaffham Bul- 
beck, the situation of which place is about 8 miles E. N. E. of 
Cambridge. 
Art. XIII. Notice of a singular Appearance of the Rainbow. 
By E. G. 
Sir, 
Tue following account of a singular appearance of the 
rainbow (fig. 133.), which was seen 14th September last, at 
a quarter past five 
P.M., on the shores of 
the Solway Frith, in 
Cumberland, may per- 
haps be interesting to 
some of your readers, 
should you think it 
worth insertion in your 
D Magazine : — 
* This circumstance is in exact agreement with the observations of 
Wells. (Essay on Dew, p.43. and 61. 
