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13.3 Frof, Cleaveland'^s description ofHalos and Parhelia, 



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Remarks on fyitre I . 

 It is much to be regretted, that circumstances prevented the 



ose of instruments on this occasion. 



The preceding figure, pro- 



jected by the eye, is designed^ for about 15 or ^0 minutes past 10 

 o'cl. A. M ; at which time all the halos and parhelia were visible, 

 the altitude of the sun heing somewhat less than 40°. The gene- 

 ra! appearance had, however, remained nearly the same for at least 

 SO minutes previous to this time. 



The parhelia s, s, were apparently about 45" from the sun, and 



fr size nearly the same, as that of the 

 The parhelia d, d, were, by estimai 



about 00" fro 



} 



and their size nearly the same ; their light was mild, and the eye 

 dwelt on them with peculiar pleasure. 



The wUte halo DFSE was not far from SO" in diameter 5 

 it passed through the sun's disc, parallel to the horizon, and ap- 

 parentlj had the zenith for its centre ; if so, its real diameter must 



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have varied, as its radius would he the sun's zenith distance, 

 which was constantly diminishing. 



The centre of BOIN" 



til 



and 



diameter of 



this halo was between 44" and 50". 



_ J 



The centre of ABC is supposed to he at the parhelion I ; some 

 observers thought, that this halo was elliptical ; but this appear- , 

 ance was probably an optical deception, arising from the relative 

 size and position of the halo in regard to BOIN. 



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The arcs K and L very probably had the parhelion I for their 

 centre, one of them passing through Z, and the other, perhaps, a 

 tangent (o the white halo at D; but it is impossible to determine 



this poi 





