150 Disturbance of the Earth’s Magnetism. 
the zenith, which appeared clear and compact for some time, when it 
began to move, and darted forth rays in every direction like crystals. 
March 6, 1832. 
Since the foregoing was communicated to the Institute, several 
particulars have been learned in reference to the subject, which, on 
some accounts, are deemed interesting. ‘The Annual Meteorological 
Reports of the different Academies in the State of New York, to the 
Regents of the University, have been received; and from them it 
appears that the aurora of the 19th of April was visible over the 
whole extent of the State, and probably considerably west of it. It 
is described as being very brilliant at Lewiston on the Niagara river, 
extending high, and farther to the south than any before observed. 
In the eastern part of the State, it was seen at most of the Acade- 
mies along the Hudson, and at Erasmus Hall on Long Island. It 
also appeared brilliant at Potsdam in St. Lawrence county, the most 
northern Academy in the State. It was probably not seen very ex- 
tensively in the States east of New York, as I am informed the weath- 
er in the eastern part of New England was cloudy at the time, ac- 
companied with rain. The aurora is described as shooting up to the- 
zenith at North Salem; and at Middlebury as consisting of corusca- 
tions in almost every part of the visible heavens. At Fairfield, it 
illuminated nearly the whole heavens; a number of bows, commen- 
cing in the northwest, passed south of the zenith, and terminated in 
the northeast. An interesting account is given of its appearance at 
Utica, where it is described as rising at one time in streams of light, 
of purple, yellow, green and other colors, and exhibiting a rapid hori- 
zontal motion, passing and repassing like a company of dancers. ‘The 
actual intersection of the beams so as to form the appearance called 
the corona, is mentioned as having been. seen in the city of New 
York, at Hartwick, Cherry Valley, Hudson, and Prattsburgh in Steu- 
ben county. 
The only plausible explanation of the formation of the corona, is 
that which supposes the beams of the aurora to consist of cylindrical 
portions of some kind of matter, which becomes luminous as it passes 
into the higher regions of the atmosphere; and that the cylindrical 
beams shoot up from many points of the earth’s surface, nearly par- 
allel to each other, and in the direction of the dipping needle. Being 
at different distances from the observer, they appear of different ele- 
vations ; and sometimes, . when seeming to overlap each other, they 
