From John Bartram
Extract:1 The Royal Society
[Philadelphia, November 12, 1757]
Here is a visible Aurora Borealis; at 7 a Clock it was about two hours high, to the northward pretty bright. Soon after Day light disappeared it was much more East, where it was redder with some faint streamers, whose Points reached near 45 Degrees Elevation, which soon disappeared, and the Light descended by Degrees under the Pole, and by 10 a Clock was near extinct. I should be very glad to know whether (and how) it appeared this Night with you, which may assist in some Philosophical Enquiries. I have not observed any this Fall before. Yesterday the Weather was cool and clear, and the Wind pretty strong at North; and I believe this the coldest Evening we have had this Fall, tho’ this Week we had Ice as thick as a Dollar.2
1. In BF’s hand; he apparently made this extract to read before the Royal Society, Feb. 25, 1762; it was printed in Phil. Trans., LII (1762), 474. BF had entitled the paper “Extract of a letter from Mr. John Bartram of Philadelphia to Mr. Franklin in London dated Nov. 12. 1757,” but when published the final words were revised to read “… to Benjamin Franklin LL.D. F.R.S. relating to a remarkable Aurora Borealis.”
2. See below, p. 358, for BF’s reply. No other reports of this aurora have been found.