736 EEPORTS OF ASTRONOMICAL OBSERVATORIES. 



WiLHELMSHAVEN, Germany. 

 Kaiserliches Marine Ohservatorium. 



Longitude from Greenwich, 32^ 35^21 E. 



Latihide, 53° 31' 52".2 :N". 



Authority for longitude: Astronomische Arbeiten des kgl. preuss. 

 geodatischen Instituts fiir 1878. Latitude, own observations of zenith- 

 stars with meridian circle. 



Director: C. Borgen, Dr. phil, 187G; 



Assistants : P. Andries, Dr. phil. ; 



Lieutenant zur See, Hartmann. 



Founded in 1875 ; comi^leted in 1878. 

 Instruments : 



{a) Meridian circle: one; makers, A. Eepsold Sohne, in Hamburg; 

 diameter of circles, 21.6 inches, divided to 2'; read by 4 microscopes, 

 each to 0".l; aperture of objective, 4J Inches; magnifying jiower ordi- 

 narily employed, 125 diameters. 



{h) Meridian transit instruments : one portable, by 0. Bamberg, Ber- 

 lin ; aperture, 1^ inches. 



(c) Equatorial instrumeiits : one, by Steinheil Sohne, in Munich; 

 aperture of objective, 4 inches; magnifying powers of eye-pieces, 48 to 

 360; ring-micrometer, (c') One, Steinheil Sohne; 2^ inches aper- 

 ture; magnifying power, 24 to 150. 



(/) Chronograph : one, by FuESS, Berlin. 



{g) Clocks: meantime; one, by Eppner, Berlin; sidereal; one, by F. 

 Tilde, Berlin (standard clock). 



(i) Miscellaneous : A complete set of Lamont's instruments for ob- 

 serving the variations of the magnetical declination, horizontal force, 

 and inclination. 



Lamont's magnetical theodolite; dip-circle by Dover; self-register- 

 ing barometer and anemometer (Robinson); meteorological instru- 

 ments; self registering tide-gauge; time-ball. Since September, 1880, 

 a self-registering tide-gauge, devised by Mr. Reitz, of Hamburg, has 

 been erected in Heligoland and placed under the control of this Observ- 

 atory. 



Observations during the past year (1880): 



(«) Observations for time and determination of places of the occulta- 

 tion-stars of the IS^autical Almanac. 



(b) Only used for practical instruction. 



(c) (c') Comet Swift (1880 c). Occultations of stars. 



{i) Meteorological observations (three times a day, usual weather re- 

 cording and registering of barometer and anemometer, read hourly), 

 magnetical observations; every second hour from 8 a. m. to 10 p. m. 

 readings of the variation instruments, and every month one or two ab- 

 solute determinations of magnetic elements. Tide registerings here and 

 in Heligoland. 



