158 Notes to the Extra Observations of Magnetometers, February 11 — October 20, 1844. 



NOTES ON THE AUROR^E BOREALES. 



28. 



April 



12 51. 



Faint auroral light ? 14'' 5". Faint auroral light ? 



Very faint auroral (?) light to NNW. 



Sky milky to W. Aurora I Bright moonlight. 



Band of auroral light to N. 8'' 30"'. Brightest to N by W. ; streamers from NNE. 9'' 0"'. Auroral 



arch about 5° altitude. Faint streamers from N by W. 9'' 35°'. Streamers. 

 Rather bright auroral light to N. 



Faint auroral light. 35"". Auroral light gone. 12'' 0'". Clear to N., and no aurora visible. 

 Jwidently a bright aurora, with streamers, but scarcely visible on account of the bright moonlight. 

 Fine auroral arch. Azimuths of extremities 35° and 286°, counting from N. to E., S., and W. ; 



altitude of lower distinct edge 11°; breadth of the luminous arch at the magnetic meridian 5°. 

 Pencils of aurora within the arch at the azimuth 327 . Lunar corona. Yellow portion 2°-7 diameter. 

 The auroral arch has fallen in at azimuth 340" ; it has a cycloidal termination at azinmtli 301°, and 



slopes off gradually to E. 

 Faint streamers due N. Much of the inner edge of the arch is now nearly a straight line. 

 Faint streamers continue at the N. Arch briglitest at azimuth of 317°. 



Auroral arch fainter ; cycloidal termination at azimuth 322° ; the arch slopes gradually from the meri- 

 dian to near the horizon at the eastern extremity, azimuth 30°. 

 Pencils at azimuth 326°. SI"". Pencils at the W. exti'emity, azimuth 328'. Aurora much fainter, 

 losing the character of an arch — nearly amorphous and fallen in at 0° azimuth, where there is a 

 bright point ; patches of cloud cross from eastwards. 

 Bright at 3° azimuth. Flickering. 46"". Faint diffused light. Aurora a little more to W. now. 



Streaks of fine cirri to NE. (1) 

 The auroral arch now extends from azimuth 280' to azimuth .5°; much brighter than at 12'' 46'". 



Bright at azimuth 325°. 

 Pulsations of atu'oral arch, with waves of light. 

 The aurora very faint; moon due W. Corona much mure distinct; yellow ring previously measured; 



blue external ring now very visible ; whole diameter about 5°. 

 A few streaks of fine cirrus. The aurora very faint. 

 Auroral streamers to NNW. No arch. 12*' 11"'. No streamers visible. 24'". The same. 45'". 



Auroral light to N. 

 Fine auroral arch. 1 S*" 6™. Aurora in detached patches of faintish light at different altitudes to NNW. 



Brioht moonliirht. 

 No aurora visible. 14'' 40'". The same. 16'' 6'". A band of auroral light to N. 

 Faint auroral streamers seen, ll*" 0"". A nearly homogeneous auroral light covers a great part of the 



sky to N. 12'' 0"'. Auroral light still visible. 

 Auroral light to NNW. ? 12'' 5'". Auroral light to NNW. 

 Slight auroral light (?) to N. 

 Very light to N. 

 Aurora seen at Whitehaven, mentioned in Jameson's Edinburgh New Philosophical Journal, April 



1845. 

 Auroral light or twilight to N.? 



Aurora seen at Whitehaven this evening, see Jameson's Journal for April 1845. 14'' 30'". Appear- 

 ance somewhat like an aurora to NW. Many falling stars. 

 Cirri. Belt of auroral light, altitude 4°. 8'' 50"'. Auroral belt, 5° altitude. 10''. Belt of auroral 



light ? 

 Sky clear, but no aurora visible. 10'' 10'". Very faint auroral light? 11'' 15"'. Faint aurora. 



Streamers at 11" 10""? 

 Auroral arch extending from azimuth 208" to 108", altitude 9" ; throwing up streamers at 8"' from 

 azimuth 137° and 174", to an altitude of from 15° to 20° ; the centre of the arch is at about 340" 

 azimuth : at 11"'— 12°' several bright streamers at the azimuth 310°— 315" moving rapidly towards 

 the E. The aurora must have commenced to be visible about 14'', as it was not noticed at 13'' 58™. 

 24'". Aurora now more diffuse and interspersed with bi-ight patches, altitude about 15". 41'". Aurora 

 faint and amorphous. 



