HI, An Account of a (pyramidal Appearance in the 
HeaPens , ohferVed near Upminfter in EffeXj by 
the Ppyerend Mr. William Derham, K $?. S. 
Vpmwjlcr, April 7. 1 707. ' 
HjjH'BE Afternoon of Thurfday April 3. Taft, I devoted in" 
J| fomemeafure to the Service of the Royal Society, to 
take Angles, in order to finifh my Obfefvations about 
Sounds. And as l was returning home, I perceived in the 4 
Weftern part of the Heavens, about a quarter of an Hour 
after Sun- fet, a long flender Pyramidal Appearance , per-' 
pendicular to the Horizon. The Safe of this Pyramid I 
judged to be doubtlefs the Sun (then below the Horizon.) 
Its Apex reacht 15 or 20 Degrees above the Ho-' 
rizon. It was throughout of a rufty red Colour 5 and 
when Ifirftfa^v it, pretty vivid and ftrong ^ but the top- ' 
part fainter much than the bottom, nearer the Horizon. 
At what time this Appearance began, whether at, or how 
foon after Sun- fet, 1 cannot fay, being at that time in a 
Friend’s Houfe. But about a quarter of an Hour after 
Sun-fet, as foon as I was gotten abroad, I perceived if, 
and had for fome time a fair Profped of it, the Horizon 
being pretty free and open where- I then was. But after 
a -while, it grew by degrees weaker and weaker, fo that in ; 
about a quarter of an Hour after! firft faw it, the top- 
part- (ai-b. d. in Fig. 1.) was fcarce vifible. But the lower 
] part remained vivid ranch longer, but yet grew by degrees' 
shorter and fhorter. Ffaw the Remains of the lower half 
(k d- e.f ) a fall Hour after Sun-let 5- and fhould per- 
haps have feen it longer, had the Horizon been open, Muf - 
it: was often in my Walk pent up with Trees, which not 
