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A LETTER to the i?fu. HENRY USSHER, D.D.from 

 the Rev. JAMES A. HAMILTON, D. D. M.R.LA. 

 giving an Account of PARHELIA feen at Cookji< 

 September 24, 1783. 



own 



Cariff, January 20, 1786. 



Dear Sir, 



JL BEG leave, through yon, to communicate to the Royal Irifh Read Fe- 

 Academy, the following very curious optical phaenomena which I jl'g".^ ' 

 obferved September 24, 1783, at Cookftown, where I then 

 refided, and paid a pretty regular attention to aftronomical and 

 meteorological obfervations. 



Wednesday, September 24th, 1783, as I was preparing to 

 obferve the fun paffing the meridian, before the ift limb touched 

 the centre wire, it was obfcured by a dark well-defined cloud, 

 about 10° in diameter. Upon going to the door of the tranfit 

 room, to fee if it was likely foon to pafs off the diflc of the fun, 

 I obferved the following phaenomena : 



From 



