REPORTS OF AMERICAN OBSERVATORIES. 557 



Location of observatory : (City) New Haven; (County) New Haven; 

 (State) Connecticut. 



Name of observatory : The Sheffield Scientific School of Yale 

 College. 



„„ , . , i Longitude from Washington, h 10 m 30 8 .0 E. 



Ot equatorial J ^.^ 410 m 36 „ 5 K 



Authority for latitude and longitude : Latitude from observations with 

 zenith telescope by C. S. L. Longitude, Coast Survey. The Coast 

 Survey latitude is 41° 18' 40".67. 



I. Personnel: 



Director, C. S. Lyman. 

 Assistant, WlLLTAM Beebe. 



II. Instruments: 



(a) Meridian circles : Makers, Ertel & Sons, 1845. Altered by Wm. 

 J. Young, 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; mag- 

 nifying power ordinarily employed, 190 diameters; focal length, 58.2 

 inches. 



(b) Meridian transit instruments : Makers, one by C. S. L., of 30-inch 

 focal length; aperture, 2.0 inches; magnifying power, 185 diameters. 

 Circle, 12 inches, reading to 10" by verniers. It has declination microm- 

 eter and fine level, for use as zenith telescope, made in 1852-53. 



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

 of objective, 9 inches; magnifying powers of eyepieces, 40, 80, 140, 200, 

 280, 450, G20. 



{&) Portable 4g-inch refractor by Messrs. CLARK & Sons. 



(d) Spectroscopes : By A. Clark & Sons, of 7 prisms twice traversed. 

 (/) Chronographs : One just finished by A. Clark & Sons. 



(g) Cloclcs : Sidereal; makers, 1 by Appleton, London, and 1 by E. 

 Howard & Sons, Boston. 



(h) Chronometers: Sidereal; maker, Poole, improved by Negus. 



(i) Miscellaneous: 1 bi-filar position micrometer by Dollond ; 1 mul- 

 tiple ring micrometer (8 rings); 1 patent sextant by Pistor & Mar- 

 tins; 1 patent reflecting circle by Pistor & Martins. Yale College 

 has also a 10-foot refractor of 5-inch aperture by Dollond, and a 5-foot 

 transit instrument of 4-inch aperture by Troughton & Simms. The 

 former is in charge of Professor Loomis, the latter not mounted. 



III. Observations during tiie past year (from September, 

 1878, to September, 1 879) : 



(b) (b') Time observations for city and chronometers of the port. Prac- 

 tice of students for time, latitude, longitude, etc. 



(c) (c') Observations of Bkorsen's and Swift's comets, etc. 



