Latour Marliac, of Temple-sur-Lot, France, some of the most favoured varieties being carnea, chromatella, flammea, ignea, rosea, Robinsoni, Aurora, blanda, &c.
He was the first, in 1867, to examine the spectrum of the aurora borealis, and detected and measured the characteristic bright line in its yellow green region; but he was mistaken in supposing that this same line, which is often called by his name, is also to be seen in the zodiacal light.
AURORA, a city of Kane county, Illinois, U.S.A., in the N.E.
Aurora is served by the Chicago, Burlington & Quincy, the Chicago & North-Western, the EIgin, Joliet & Eastern, and the Illinois, Iowa and Minnesota railways, and is connected with Chicago by an electric line.
The first settlement in the vicinity of Aurora was made in 1834.
Aurora, Missouri >>
'ABAYE, the name of a Babylonian aurora, born in the middle of the 3rd century.
AURORA POLARIS (Aurora Borealis and Australis, Polar Light, Northern Lights), a natural phenomenon which occurs in many forms, some of great beauty.
Fritz (2) has, however, drawn a series of curves which are believed to give a good general idea of the relative frequency of aurora throughout the northern hemisphere.
Starting from the equator and travelling northwards we find in the extreme south of Spain an average of only one aurora in ten years.
Between higher and middle latitudes, a primary consideration is that aurora is seldom seen until the sun is some degrees below the horizon.
There is no reason to suppose that the physical causes whose effects we see as aurora are in existence only when aurora is visible.
Until means are devised for detecting aurora during bright sunshine, our knowledge as to the hour at which these causes are most frequently or most powerfully in operation must remain incomplete.
The original gives the relative frequency of aurora for each degree of depression of the sun below the horizon, assuming the effect of twilight to be nil (i.e.
Whether there is any real difference between high and mean latitudes in the annual frequency of the causes rendered visible by aurora, it is difficult to say.
Loo 82 57 46 8 Out of a total of 1714 hours during which the sky was wholly overcast the Swedish expedition saw auroras on 17, occurring on 14 separate days, whereas 226 hours of aurora would have occurred out of an equal number of hours with the sky quite clear.
Thus there must in general be a difference between the observer's magnetic meridian - answering to the mean position of the magnetic needle at his station - and the direction the needle would have at a given hour, if undisturbed by the aurora, at any spot where the phenomena which the observer sees as aurora exist.
Relations to Magnetic Storms. - That there is an intimate connexion between aurora when visible in temperate latitudes and terrestrial magnetism is hardly open to doubt.
On some of these occasions aurora was brilliant in both the northern and southern hemispheres, whilst magnetic disturbances were experienced the whole world over.
Arctic observers, both Danish and British, have repeatedly reported displays of aurora unaccompanied by any special magnetic disturbance.
When there has been much apparent movement, and brilliant changes of colour in the aurora, magnetic disturbance has nearly always accompanied it.
In the northern hemisphere to the south of the zone of greatest frequency, the part of the sky in which aurora most generally appears is the magnetic north.
The relative frequency in the two positions seems to vary with the hour, the type of aurora, probably with the season of the year, and possibly with the position of the year in the sun-spot cycle.
General Sabine, Sir John Franklin, Prof. Selim Lemstrom, Dr David Walker (at Fort Kennedy in 1858-1859), Captain Parry (Fort Bowen, 1825) and others - have seen aurora below the clouds or between themselves and mountains.
The Swedish Expedition (17) of 1899-1902, engaged in measuring an arc of the meridian in Spitsbergen, were unusually well provided spectrographically, and succeeded in taking photographs of aurora in conjunction with artificial lines-chiefly of hydrogen-which led to results claiming exceptional accuracy.
By the blushes of Aurora and the music of Memnon, what should be man's morning work in this world?
I have been as sincere a worshipper of Aurora as the Greeks.
All poets and heroes, like Memnon, are the children of Aurora, and emit their music at sunrise.