Before me lies the draft of an electrical clock, which is styled, “The clock of all nations.” The design is an ingenious one, and serves to show at a glance the difference in time between prominent cities in all parts of the globe. For this purpose, a central dial is drafted, representing the meridian of New York. The hands on this dial indicate the precise hour of noon. Around this central figure are arranged twenty additional dials, on each one of which is marked by the hands the time of day as it will exist in the cities named, commencing on the east of New York with Pekin, and terminating to the west of it with San Francisco. By it, you perceive at a glance the precise variation of time in the different longitudes to which these cities belong. For example, while the clock of New York indicates twelve, noon, the one in Pekin indicates twenty minutes before one in the morning; the one in Rome, fifteen minutes to six P. M.; the one in London, five minutes of five P. M.; and so on until you reach New York, where it is twelve M. Then passing westward of that point, where the time is, of course, slower, the dial for Chicago marks seven minutes past eleven A. M.; that of St. Louis, five minutes of eleven A. M.; that in San Francisco, fifteen minutes before nine A. M. By this means, the variation between Pekin and San Francisco is shown to be about sixteen hours, or nearly two-thirds of one whole day. By the same method, the reader will at once discern that it is possible to locate the commencement of the day at any one of these points in its passage around the world. In order to do this, let it be supposed that the day begins when it did in Bible times, with the setting of the sun. It is, if you please, Sunday at Pekin, and those who keep that day commence to celebrate it at sunset. Now, if we would ascertain just when the citizens of Rome would enter upon a like service, it is only necessary to determine how long it would take the sunset to travel the distance separating these two cities. By consulting the draft in question, we find that the time at Rome is six hours and fifty-five minutes slower than that at Pekin. This being the case, the sunset would reach them, and they would enter upon the first day of the week just six hours and fifty-five minutes after those dwelling on the meridian of Pekin have done so.