Phllo/cphical CorrtJ}ionclenie.'~Kevi FuhUcaitom, aSf 



To Mr. Nicholson, 

 SIR, London, 22c! Augiijl 1 797. 



UPON perufing the account given in your lad number, of the phenomenon of the 

 Fata Morgana, and upon confulting the plate annexed by way of explanation, I was very- 

 much puzzled to comprehend how the fpeiflator, " placed on an eminence of the city, with 

 Lis back to the rifing fun, and his face to the fea," looking of courfe towards the weft, could 

 at once enjoy the fight of this truly admirable phenomenon, a diftant view of the •zveflern 

 afpe<£t of the city, and alfo of the mountains behind him. A few words in a future number, 

 in explanation of this Ilrange combination, will much oblii'e. 



Sir, 



Your conftant reader, 

 DAVUS. 



*»* THE difficQlty ftated by this correfpondent, together with feveral others, engaged my 

 attention at the time the account (p. 225) was drawn up : but as they feemed fcarcely ca- - 

 pable of being cleared up by reafoning, while the theory remained fo very uncertain, I 

 .thought it bed to avoid entering the ample field of cenjefture which offered itfelf. It feems 

 altogether improbable, that the rays of light fliould be rcfiecled immediately back to the 

 city, and every part of the drawing diretlly contradifts this fuppofition. I am therefore 

 inclined to conclude that the defcription, though literally tranflated, is faulty, fo far as it 

 contradicts the notion of the obferver being fo placed as to view the city over a portion of 

 the bay. I imagine that the people, when they run haftily to the fea exclaiming Morgana! 

 do not run to the ramparts of the town, but to the fouthern point of the bay, at the diftanca 

 of half a mile or lefs from the town ; whence, with the fun * behind them, they may have 

 an oblique view of Reggio flrongly illuminated, and a more direft profpeft of the northern 

 (hore of the bay. 



NEW PUBLICATIONS: 

 An Account of two Cafes of the DiaBetes Mellitus, vl-ith Remarks as they arofe during the 

 Progrefs of the Cure ; to which are added, A general View of the Nature of ihe Difeafe, 

 and its appropriate Treatment; including Obfervations on fome Difeafes depending on 

 Stomach Affotlion, and a Detail of tlie Communications received on the Subjeft fince 

 the Difperfion of tlie Notes on the firft Cafe. By John Rollo, M. D. Surgeon General, 



Royal Artillery With the Rcfults of the Trials with various Acids and other Sub- 



llances iu the Treatment of the Lues Venerea, and fome Obfervations on the Nature of 

 Sugar, &c. By WLllIam Cruickfliank, Chemift to the Ordnance, &c. in two Volumes 

 Oflavo, 14s. Dilly. 



-In this rrcatifc Dr. Rollo has confidered the diabetes mcUItus as a difeafe of the organs 

 of digcftion, and not of the kidneys; he conceives that the fugar which p'alTes off by urine 



• Tlic fun'i rays can never niAc un angle cf 45" on tlie lia at Reggio, from the aiimuih ef the image in 

 the drawing. 



