SUPPLEMENTARY PAPERS. 33 
‘that in all countries in which hours are known, the origin of those hours 
is, approximately, the mean time of local noon. There must thus be 
introduced a degree of confusion, which the ordinary sense of man- 
kind, by maintaining (in adjustments of public clocks, &c.,) the same 
mean origin within definite limits,and well defined differences between 
the indications in territories of other definite limits, has effectually 
met. Thus the difference between England and Ireland has been 
fairly met by a difference of 25™ (which would better have been 30™) 
between the indications of the public clocks. It is, I believe, certain 
that this is not the result of legislation, it appears to be merely the 
result of common sense, guided perhaps by a single personal influence. 
At Basle (possibly in like manner at other stations) the great systems 
of the French Railways meet, and there the times in the French 
States and the German States (I suppose Paris time and Berlin time), 
-are exhibited side by side, and there can be no confusion or difficulty. 
In the case of the railway from New York to San Francisco, it is 
merely necessary to frame the Westward train-bills and guard’s 
watches to New York time, and the Eastward train-bilis and guard’s 
watches to San Francisco time, with double clocks at every station, 
naturally there must be a re-adjustment of watches at the end of the 
journey. Thus, adopting as incontrovertible the idea that every district 
will refer to visible noon for the origin of its own time, and remarking 
the extreme facility with which those origins can be linked together, 
I set not the slightest value on the remarks extending through the 
_ early parts of Mr. Fleming’s paper. Secondly, as to the need of a 
Prime Meridian, no practical man ever wants such a thing. If a 
Prime Meridian were to be adopted, it must be that of Greenwich, 
for the navigation of almost the whole world depends on calculations 
founded on that of Greenwich. Nearly all navigation is based on the 
Nautical Almanac, which is based on Greenwich observations and 
referred to Greenwich Meridian, and the number of Nautical 
Almanacs sold annually exceeds, I believe, 32,000 (see the Navy 
Estimates). But I, as Superintendent of the Greenwich Observatory, 
entirely repudiate the idea of founding any claim on this. Let Green- 
wich do her best to maintain her high position in administering to 
the longitude of the world, and Nautical Almanacs do their best, and 
we will unite our efforts without special claim to the fictitious honour 
of a Prime Meridian.* For the mere expression of longitudes, with 
the limitation that longitude is not to exceed 180° East or West, 
Greenwich is not inconvenient. But every such consideration yields 
to historical or other circumstances. Thus, as regards California 
civilization and time-reckoning (in the count of days of a month) 
* The origin of Greenwich Observatory is curious. A Frenchman had a correct idea that 
longitude at sea might be determined by observations of the moon. He was not received by 
Louis XIV., but procured introduction to the Duchess of Portsmouth, who placed his scheme 
before Charles II. and his brother James, both able men in some respects. They adopted it, in 
essentials, and Greenwich Observatory was founded. The moon is still the most important 
object of the Greenwich Observatory. 
