On the Aurora Borcalis in Summer. 299 
1739. Sept. 12. 1743.Mch. 8. Very great. 
oe . Soe Apl. 1. Slight. 
1740, Mch. 12. Great. June 28. Slight. 
13. Slight. 1744. ress wr Brilliant. 
May 27. 7: 
1741. Mch. 5. 1745. Feb. 9. Great 
9. Slight. and a vty one in Feb. without date. 
21. 1746. Feb. 
June 29.* d 
July 12. Very great. Mch. 14. 
Sept. 21. Great. Oct, 7. 
+ Dec. 28. 
1742... Feb. 20. 1747. Jan. 2. Slight. 
Mch. 5. Slight. Mch. 22. 
6. Narrow zone from N. E. Nov. 21. Great. 
15. Very great. [to s.w. Dec. 6. Very great: fiery. 
16. 1748, Jan. 22. Slight. 
24. Aug. 28. Very great: fiery. 
1743. Jan.12. Great. Dec. 4. Great. 
From the above register, it appears that some of the most bril- 
liant displays of the Aurora Borealis witnessed during the period of 
record, occurred in June, July and August. 
Dr. Henry Gibbons, in a valuable essay on the Aurora Borealis, 
contained in * The Advocate of Science and Annals of Nat. Hist.” 
8vo. Philad. 1834, Vol. i. p. 21-25, gives a tabular view of all the 
Aurore witnessed by him at Wilmington, Delaware, from Aug. 28, 
1827, to the end of December, 1833, together with the meteoro- 
logical circumstances of each occurrence. This record plainly con- 
tradicts the prevailing opinion stated in the former part of this pa- 
per. The following are the dates of each instance: 1827. Aug. 
28; Sept. 8, 9, 25; Nov. 9, 18.—1828. Jan. 18; Sept. 26, 27.— 
1829. Jan. 28; March 18; Dec. 19.—1830. May 6,14,15; June 
10,11; July 14; Aug. 15, 20; Sept. 12, 15, 16, 17; Oct. 9; 
Dec. 11, 12.—1831. Jan. 6,7; Feb. 6; March 8; April 20; May 
8; June 10; July 4, 5, 10, 31; Oct. 29.—1832. Jan. 22; March 
27; Aug. 22,23; Sept.30; Nov. 14.—1833. Jan. 2; March 21; 
May 17; June 17; July 10; Oct. 13; Dec. 15. 
The Aurora has been abundant during the recent summer. It 
was observed here three times in June, seven in July, and six in 
August. There were fourteen evenings in June, seven in July, and 
ten in August, in which the sky was overcast, so that no Aurora 
could have been seen. 
* This case is uncertain. “ Arcus — igneus lucidus valde ab horizonte 
Prope S. E. ad gradus saltem 90 projectus.” 
* 
