Pico Ruivo, by Captain Sabine. 81 



tables in works of authority, such as in the Connoissance des 

 Terns, and in Professor Lax's Nautical Tables, shovHd have an 

 additional column, specifying the spot to which the latitudes 

 and longitudes refer ; it is otherwise quite unnecessary to give 

 these data to seconds of space. 



The precise geographical determination of some one spot in 

 Funchal is still a desideratum, which I was in hopes of sup- 

 plying by a sufficiency of lunar observations, could another 

 day have been spared me. I may state, as an approximation, 

 that the result of 64 distances, 40 of Regulus west, and 24 of 

 the Sun east of the Moon, observed in the Consul's house, made 

 its longitude 16° 55' 00" W. ; that the three chronometers of 

 Parkinson and Frodsliam, on which I placed principal reliance, 

 made it respectively as follows : 



By observations in the fore and after- 

 noon, and using the rates at which they 

 had gone in England. 



aad that the mean of all the chronometers I had with me, (except 

 Brequet's whose rate had altered considerably,) made the 

 longitude 16° 56" 30." 



Note. — Since this letter was written, Madeira has been visited by his 

 Majesty's ships Leven and Barracouta, on their passage to survey the 

 eastern coast of Africa, under the con\mand of Captain Owen. By the 

 chronometers on board these ships tlie difl'ercnce of meridians between the 

 Marine Observatory at Lisbon, and the Loo Fort in Funchal Bay, ap- 

 peared 7° 48' 09", whence assuming- the Observatory at Lisbon at 9° 08' 51" 

 W., the Loo Fort would be in 1C° 57' 00".— And finally, the longitude of 

 the Consul's garden at Funchal has been determined by a mean of sixteen 

 chronometers, specially sent for the purpose, at the direction [of the 

 Commissioners of Longitude. It is understood that their mean result 

 made the garden in ICo 54' 52". 5 W. The three stations are all within a 

 second of time. 



"I conclude with a detail of the observations, and theheiglifs 

 computed from them. 



Vor.. XV. G 



