The charts constructed upon this meridian cover the whole navigable globe. The cost of the plates from which these charts are printed is probably 75 per cent. of the cost of all plates in the world for printing mariners' charts, and is probably not less than ten millions of dollars. As a matter of economy, then, to the world at large, it would be better to permit those plates to remain unchanged which are engraved for the meridian of Greenwich and to make the necessary changes in all plates engraved for other meridians. A very natural pride has led the great nations to establish by law their own prime meridian within their own borders, and into this error the United States was led about 35 years ago. Should any of us now hesitate in the adoption of a particular meridian, or should any nation covet the honor of having the selected meridian within its own borders, it is to be remembered that when the prime meridian is once adopted by all it loses its specific name and nationality, and becomes simply the Prime Meridian. Mr. RUTHERFURD, Delegate of the United States, stated that he did not propose to take up much of the time of the Conference; that he had listened with great pleasure to the exhaustive speech of his colleague, Commander SAMPSON, but that he wished to say a few words about the conditions of permanence in the prime meridian to which allusion had just been made. He said that he would call attention to the fact that the observatory at Paris stands within the heart of a large and populous city; that it has already been thought by many of the principal French astronomers that it should no longer remain there; that it has been, interfered with by the tremors of the earth and emanations in the air, which prevent it from fulfilling its usefulness; that for several years past strenuous efforts have been made to remove the observatory from Paris to some other place where it may be free to follow out its course of usefulness, and that the only thing which keeps it there is the remembrance of the honorable career of that observatory in times past. He added that he was sure that there was no one here who failed to recognize its claims to distinction; that there was no one here acquainted with the past history of astronomy but looks with pride upon the achievements of the human intellect effected there. At the same time, however, if a change is to be made, if sentiment should give way to practical reason, a locality, no doubt, will be found which may be calculated to fulfil the requirements of a prime meridian better than that one.