3 '9 2683 3 2 0

On a new variable sbar in Cygnus. I beg to announce the discovery of variability in the red star, No. 587 of Birmingham's Catalogue of Red Stars.

The variation 5m8 to 71'5, with a period of 250-300 days, but further observations will be necessary to

The star was at a maximum at the end of December 1884; at a minimum early in The variability has been confirmed by Mr. Edwin F.

The star lies a few minutes of arc s.f. Q Cygni, and is identical with Lal. 42153 and DM. +44"3877. seems to be from about determine the period exactly, June 1885, and at present it is not far from a maximum again. Sawyer of CamGridgeport, Mass., U. S. A.

Ballysodare, Co. Sligo, Ireland 1885 Sept. 9. Y. E. Gore.

Z 11 s a t z. Nach einer Mittheilung von Dr. Deichmuller lauten die Grossenschkmngen der DM. : 1856 Oct. 2 5 Krueger 6.7m 1856 Oct. 2 7 Schiinfeld 7 1859 Mai 1 3 Schonfeld 6.7

agreed in making the longitude of Cordoba nearly 4' less

Ausserdem ist der Stern in den Bonner Zonen der A. G. beobachtet: 1873 Aug. 1 7 Fabritius 7mo 1875 Nov. 3 Seeliger 6.2

! Observatory is given in the Introduction referred to as

KY.

On the Longitxide of the Cordoba Observatory. In the Introduction to the fifth volutne of the Cor-

doba Observations, of which a limited number of copies was distributed among astronomers in April last, the final chapter consists of a short discussion of the Longitude of the Observatory. The differences of longitude determined by telegraphic exchanges made with Mr.Moneta at Buenos Aires in 1872, with Mr. Vergara at Santiago de Chile in 1874 and 1875, and with Lieut. Com. Davis at Valparaiso in 1883, were as follows:

Cordoba - Buenos Aires = oh 2 3m1 8238 & oS03 Santiago-Cordoba = o 25 57.9 Valparaiso - Cordoba = o 29 46.20 k 0 . 0 4 .

The determination with Santiago was not fully satisfactory, some of the sheets containing the observations for instru- mental correction having been lost in the transmission from Chile; but the largest possible error of the result was esti- mated as 0f20.

The measurements subsequently made by the U. S. Naval Expedition under Capt. Green gave for the Buenos hires station

Buenos Aires - Greenwich = 3h53m2gf3~

whence we derive for the Cordoba meridian-circle, by way of the East

Cordoba - Greenwich = 4h I 6"485 I 9.

The values used for the longitudes both of the Santiago Observatory and of the station at Valparaiso occupied by Mr. Davis, depended upon an old determination of another point in Valparaiso, deduced from chronometer- comparisons and moon-culminations; and these two values

Since the printing of the Introduction referred to, I have had the pleasure of receiving from Lt. Com. Davis the definite results for the longitude of his Valparaiso station, as determined, by way of Panama, by the U. S. Naval Expedition under his direction. These results, which he had courteously sent me from Washington, as soon as they had been established, arrived at Cordoba just after my departure, and, of course, too late to be incorporated with the foregoing values. They have since then been published.

From these we have, as the longitude of his station

Valparaiso - Greenwich = 4h46m34?44

making the longitudes of the various points in Valparaiso and of the Santiago Observatory larger by 3?94 than those previbusly accepted. And we thus obtain for the Cordoba meridian-circle by way of the West

Cordoba - Greenwich = 4h ~6~48f24.

The accordance, within the twentieth part of a second of time, between the determinations - as made by the way of Lisbon, Rio de Janeiro and Buenos Aires, on the one hand, and by the way of Washington, Panama and Valparaiso on the other may be regarded as leaving nothing to be desired; and we therefure adopt as the definite value of the longitude of the Cordoba meridian-circle

4h I 6"48f2.

The corresponding longitude of the Santiago Ob-

The final value for the latitude of the Cordoba seryatory will be 4h 42m46?3.