1 882. 93 Trans. N. V. Ac. Scz. 



of the day be only continuously numbered from beginning to end, and 

 there will never be any uncertainty as to which part of the day is 

 meant. 



Another of the secondary features of the scheme is the designation 

 of a zero meridian. The zero meridian is that from which terrestrial 

 longitudes begm to be reckoned, and that at which, at the close of the 

 day, the count of the day in the monthly calendar shall be momentarily 

 the same for the entire globe. Any meridian which might be chosen, 

 and which should be generally accepted, would answer for this 

 purpose ; but such a selection ought not to be made through mere idle 

 caprice. Regard should be had to usages actually existing ; and if 

 there is any meridian which has already become more familiar than 

 any other to the great majority of mankind, that circumstance should 

 be counted in its favor. In a contribution made by me some ten years 

 ago to a provisional code of international law drawn up under authority 

 of a resolution of this Association, by the Hon. David Dudley Field, 

 afterwards President of the Association, I endeavored to assign some 

 reasons why the meridian of Greenwich is entitled to be regarded as 

 rightfully the first meridian for purposes of longitude. But the same 

 reasons apply with equal force to the inferior meridian of Greenwich— that 

 is to say, to the meridian twelve hours distant in time, and i8o degrees 

 distant in longitude from Greenwich itself; and as I have found, in 

 consultation wirh others, that there might be danger of awakening 

 national susceptibilites by insisting on Greenwich (though, for myself, 

 I fail to find this consideration serious), I have yielded my first opinion, 

 and propose to fix the first meridian for time and for terrestial longitude 

 at the i8oth degree from Greenwich, so that this first meridian will 

 fall almost entirely upon the ocean. As in the monthly calendar the 

 change of count must begin at some particular meridian, it is desirable 

 that this change shall take place, if possible, beyond the limits of all 

 habitable lands ; and this is true of the meridian proposed, since, 

 except a small portion of wild and desolate sub-arctic Kamschatka, it 

 scarcely touches any portion of the earth's surface uncovered by water. 

 At this assumed first meridian, therefore, the day in ordinary 

 chronology will begin when the mean sun is on the meridian of Green- 

 wich ; so that in fact it will be identical with the astronomical day as 

 reckoned at that observatory. 



The last of the secondary features of the scheme which I have to no- 

 tice, is the proposition to establish, for purposes of pure chronology, 

 and for the facilitation of synchronous observations in science, a special 

 time-reckoning under the name of cosmopolitan tz'tne. So long as the 

 dimensions of the known world were limited in longitude between the 

 Indies on the east and the Canary Islands on the west, there was ng 



