1820.] Scientific Intelligence. t^ 



Zach found it. . . 28° 2' 0-0'' E. from Ferro 

 Inghirami.. 28 4 1-2 



DifFerence 00 2 1-2 



This difference, though much greater than the former, is not 

 80 surprising. 



Inghirami was much mortified at these discrepancies, which he 

 considered as throwing a slur upon the accuracy of his opera- 

 tions. He, therefore, used every possible exertion to get rid of 

 them. At first, he rested satisfied with a short base which 

 Baron von Zach had measured during his observations, to deter- 

 mhie the latitude of Florence ; but he afterwards measured a 

 much longer one himself, and went over all the parts of his 

 calculations again and again with the most scrupulous attention ; 

 but his efforts were unavailing. Baron von Zach considers the 

 error to lie in the astronomical observations. He is of opinion 

 that astronomical instruments, notwithstanding the great accu- 

 racy with which they are now made, are not capable of giving 

 the true latitude nearer than two or three seconds. Another 

 cause of the difference, he thinks, may be the attraction of 

 mountains, or of masses of matter below the surface of the earth, 

 having a greater or smaller specific gravity than usual, which, 

 by acting on the plumb line, must occasion an eiTor in the 

 astronomical observations. A third cause, he conceives to be 

 the irregidarity of the figure of the conformation of the earth. — 

 (Correspondence Astronomique, Geographique, Hydrographique 

 et Statistique, du Baron de Zach, vol. i. p. 1. Genoa, 1818.) 



III. Positions of different Places on the North Coast of Africa. 



Capt. William Henry Smyth, of Royal Navy, at present, 

 employed in the Mediten-anean in an astronomical, geographical^ 

 and hydrographical mission, has determined the latitudes and 

 longitudes of the following places on the north coast of Africa as. 

 follows : 



Tripoli (house of the British Consul) 

 Leptis magna (tent in the ruins) . . . 



Gherrza (at the tombs) 



Cyniphus (river, mouth of) 



Asal Amrah (the point) 



Benhouleat (the castle) 



Cape Bon (the tower.) 



Pantellaria island (the castle) 



Tajoura (the point) 



Galita island (the centre) 



North latitude. 



Longitude East 

 from Fcrro. 



32° 54' 13",30° 50' 30" 



32 37 23 |31 47 15 



30 37 30 |31 48 30 

 32 33 25 31 54 20 

 32 51 5 ,31 30 



31 28 10 30 58 

 37 4 45 j28 43 45 

 29 35 5 36 51 15 



32 53 31 ] 18 

 37 32 30 .26 34 50 



£2 



(Ibid. p. 68.) 



