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English Arctic Expedition, 1875–76. Instructions for use of officers. Appendix B. Capt. Sir G. Nares’s report. True Auroræ seldom observed, and displays faint. Citron-line observed on only two displays. Appendix C.

In anticipation of the starting of this Expedition, some instructions for the use of the officers in connexion with the hoped for display of brilliant Auroræ were prepared:—as to general features of the Auroræ, by Professor Stokes; as to Polarization, by Dr. William Spottiswoode; and as to Spectrum work, by Mr. Norman Lockyer and myself. As these instructions were somewhat elaborate, and will apply to all Auroral displays, I have supplied a copy of them in Appendix B. They were unfortunately not brought into requisition, for want of the Auroræ themselves. Capt. Sir George Nares has reported to the Admiralty, under date 5th December, 1877, as follows:—“Although the auroral glow was observed on several occasions between 25 October, 1875, and 26 February, 1876, true Auroræ were seldom observed; and the displays were so faint, and lasted so short a time, and the spectrum observations led to such poor results, that no special report has been considered necessary. Although the citron-line was observed occasionally, on only two displays of the Aurora was it well defined, and then for so short a time that no measure could be obtained.” (For Sir George Nares’s further Report see Appendix C, containing extracts from blue-book, ‘Results derived from the Arctic Expedition, 1875–6.’)