140 LONGITUDE AND TIME-RECKONING. 



kova, near St. Petersburg. "Washington was adopted by the United 

 States, and the charts of that country are still constructed with 

 Washington as a first meridian, although Greenwich is now used 

 for reckoning longitude by all sea-going ships carrying the United 

 States flag. The Italians selected Naples ; and ships of the empire 

 of Brazil reckon in part from Rio de Janeiro. 



An earnest desire has frequently been expressed for the determi- 

 nation of one prime meridian common to all nations, but all attempts 

 for its establishment have failed. On all sides there has been an 

 adherence, with moi'e or less tenacity, to the arbitrary zeros adopted 

 or suggested by the national navigators. Recommendations have 

 however from time to time been made in the general interests of 

 science, which is unconfined by national boundaries and unprejudiced 

 by national vanity. Some astronomers have proposed Alexandria, 

 from its being the place to which Ptolemy's observations and compu. 

 tations were reduced. The Great Pyramid has also been proposed as 

 the point through which the world's prime merid ian should be drawn ; 

 it has found an earnest advocate in Professor Piazzi Smyth, Astro- 

 nomer Royal for Scotland. 



Other astronomers have proposed that a meridian should be 

 established from celestial phenomena, so that national sensitiveness 

 shall in no way be hurt. Laplace recommended the adoption of a 

 universal first meridian, upon which it was 12 o'clock when the sun 

 entered the point of the vernal equinox in the year 1250, in which 

 the apogee of the earth's orbit coincided with the solsticial point in 

 Cancer. According to Maury, such a universal meridian would pass 

 about 8 miles west of Cape Mesurada, on the coast of Africa. 



This initial meridian was favoured by Herschel. It is certainly 

 suggested by no local circumstances such as noon or midnight, or by 

 the observatory or metropolis of any nation. Its determination is 

 made solely by the motion of the sun among the stars, in which all 

 the nations of the earth have a common interest. Herschel designated 

 the time reckoned by this meridian " Equinoctial time." But this 

 meridian possesses no one advantage not common to all other 

 meridians, beyond being perfectly free from national relationships. 



The initial meridian for the world should be chosen for other 

 reasons than any of those which, as far as I know, have yet been 

 advanced. In another place I have shown that it would be the 

 separating line on the surface of the earth, between two consecutive 



