REPOETS OF ASTRONOMICAL OBSERVATORIES. 031 



Observations during the past tear (from November 1, 

 1879, to November 1, 1880) : 

 [a) Observations for clock error; determinations of absolute places 

 of 109 stars ; observations for difference of longitude, Cambridge and 

 New Haven. 



{!)') Photometric comparisons of stars visible to the naked eye ; about 

 40,000 observations made. 



(c) (c') Micrometric and photometric observations of the satellites of 

 Mars (including 1,103 position angles and 245 distances) ; photometric 

 observations of 41 eclipses of Jupiter's satellites ; observations of iilan- 

 etary nebulte ; discovery and examination of stars with unusual spec- 

 tra ; observations of variable stars, comets, asteroids. 



Work proposed for the coming tear (1880-'81): 

 Continuation of observations now in progress. 



Principal publications of the observatort during the 

 TEAR 1879-80 : 



1. Annals of the Observatory, vol. xi, part i, 1879. 



2. Annals of the Observatory, vol. xi, part ii, 1880. 



3. Annals of the Observatory, vol. xii, 1880. 



4. Thirty fourth Annual Eeport, 1880. 



5. E. C. Pickering, Dimensions of the Fixed Stars, published in vol. 

 xvi of the Proc. Amer. Acad., 1880. 



C. W. A. EoGERS, Standards of length, published in vol. xv of the 

 Proc. Amer. Acad., 1880. 



Cambridgeport, 3fass. 

 Private Observatory. 



Longitude from Washington, 23°^ 49« E., approximately. 



Latitude, 42° 21' 56" N., approximately. 



Director: E. F. Sawter. 



For the past four years the director has been principally engaged in 

 recording meteoric observations, having published from time to time lists 

 of bright meteors, stationary meteors, meteor showers, &c., and has also 

 compiled two catalogues of " Radiant points of meteors," deduced from 

 some 1,100 or 1,200 meteor tracks. Has also collected a series of obser- 

 vations on the variable stars o Cetl, y Aquila, /5 Lyrce, S Ccphei, and 

 P Seuti, &c., and, under the head of miscellaneous phenomena, has swept 

 .some for comets, &c. Observations have been published in the Astr. 

 Nachrichten, Observatorv, Monthly Notices, Science Observer, American 

 Journal of Science, &c. During the coming year, generally the same 

 field of observation will be occupied. Telescopic observations have been 

 principally made with a 3^ inch Bordan, on portable equatorial stand 

 with divided circles, but no clock-work. 



