LXXIII. Extract of a letter from Mr. John Bartram, of Philadelphia, to Benjamin Franklin, LL. D. F. R. S. relating to a remarkable Aurora borealis


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LX XIII. E x tr a B  o f a L e tte r fr o m  M r . Jo h n  
Bartram, o f Philadelphia, to Benjamin 
Franklin, L L .  D . F. R . S. relating to a 
remarkable Aurora Borealis-.

Philadelphia, Nov. 12, 1757*
Read Feb. 25, IT  T E R E  is a vifible Aurora borealis •$,

17̂ 2, J£”j [  at feven o’clock, it was about two
hours high, to the northward pretty bright, Soon 
after daylight difappeared, it was much more ead, 
where it was-redder, with feme faint dreamers, whofe 
points reached near forty-five degrees elevation, which 
icon difappeared, and the light defcended,, by degrees* 
under the pole, and by ten o’clock was near extin&v 
I lhould be very glad to know, whether (and how), 
it appeared this night with you* which may afilft in 
fome philosophical enquiries. I have not. obferved? 
any, this fall, before. Yederday, the weather was cool? 
and clear* and the wind pretty drong. at north.; and* 
I believe this the colded evening we have had this fall* 
though this week we had ice as thick as a dollar.

Extract of the Anfwer to the above ..

London, Jan. 11, 1758..
1  T hank you for your account of the Aurora. A very. 
*  confiderable one appeared here the Tame evening,, 
being Saturday, November 12. I  did no t f e  it, but 
have heard of it from feveral. I f  it was the fame, that' 
you law, it m ud have been very high, or very extern- 
five* as the two places are 1000 leagues afunder.

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