52 HAND-BOOK OF WASHINGTON. on a second trial of another year it rarely fails to pass. There are from 60 to 100 Chronometers al ways in this room, all of which are daily wound, and compared and treated in the manner described. Thus a complete and minute history is kept of each one. , Here also are conducted the celebrated re searches connected with the “Wind and Current Chartsthe habits of the Whale, and a variety of phenomena connected with the great deep. The National Observatory of Washington oc cupies a high rank among the Observatories in the world, there being but one—that of Russia —superior to it. The largest telescope, called the Equatorial, is a 14 feet Refractor, with an object glass of 9 inches. It is mounted in the revolving dome on the top of the main building, and is so arranged with clock work and Machinery, that being di rected to a star in the morning, it may be left alone, when on returning to it in the evening, it will have followed the path of the star so exactly, that it will be found still pointing to the star, and the star will be visible through it. With its powers the stars are visible at mid-day. In one room below are the Meridian and Mural