artlonomical observatories. 391 



New Haven, Connecticut. 

 Winchester Observatory of Yale College. 



Longitude from Wa-shingtou, ()'' 16'" 30. l« E. 



Latitude, 41° 18' 30.5" N. 



Aiitliority for longitude : U! S. Coast Survey. For latitude : Zenith tele- 

 scope observations in 1857-'58. (See Am. Jour, of Sci., vol. 30, 

 p. 52, second series.) Coast Survey latitude, 41° 18' 10" G7 N. 



Directors: E. LooMis, 1831. 



D. Olmstead, 1836. 

 C. S. Lyman, 1847. 

 H. A. Newton. 



The horological bureau is a department of the Winchester Observ- 

 atory organized in January, 1880, with a special equipment of instru- 

 ments for a regular and extended public time service. The standard 

 time by law of the State is that of the meridian of the city hall, New 

 York, which is 4-" 19.6^ slow of New Haven and 12"' 10.5« fast of Wash- 

 ington. Another important work of the bureau is the testing of watches 

 and chronometers in the interest of the watch manufacture, for which 

 hot and cold closets and "other special facilities are provided. 



There is also connected with the observatory a ther mo metrical bureau, 

 in charge of Dr. Waldo, for the verification of clinical and other ther- 

 mometers. 



Instruments : 



{a) Meridian circle: Makers, Ertel & Sons, 1845. Formerly the 

 property of the U. S. Naval Observatory. Altered by William J. 

 YouNGr, 1855, and regraduated 1870. Diameter of circles, 40 inches; 

 divided to 2'; read by six microscopes to 1"; aperture of objective, 3.8 

 inches; for observations of the sun, aperture employed, 1.7 inches; 

 magnifying i^ower ordinarilj'^ employed, 190 diameters; focal length, 

 58.2 inches. 



(b) Meridian transit instruments: One made by C. S. Lyman, of 30- 

 iuch focal length; aperture, 2.0 inches; magnifying power, 185 diame- 

 ters. Circle, 12 inches-, reading to 10" by verniers; it has declination 

 micrometer and fine level, for use as zenith telescope, made in 1852-'53' 

 One by Troughton & Simms, London; aperture, 3.99 inches; magni- 

 fying i^ower, 150-200 diameters; focal length, 5.108 feet, {b') Combined 

 transit and zenith telescope, 36-inch focal length ; aperture, 2.6 inches; 

 power, 185 diameters ; 12-inch circle, reading to 10" by verniers; decli- 

 nation raicrometerand sensitive levelfor latitude work ; made in 1852-'56: 

 object-glass by Fitz, design and mounting by C. S. Ly'MAN. 



(c) Equatorial instruments: Makers, Alvan Clark & Sons; aper- 

 ture of objective, 9 inches ; magnifying powers of eye pieces, 40, 80, 140, 

 200, 280, 450, 620. {&) Portable 4'^-inch refractor by Messrs. Clark & 

 Sons. 



