257 3880 2 5 8

Nach der Ubertragung der Oppolzerschen Schwere auf den Punkt der MUnchener Beobachtungen vom Jahre 1899 ist aber

und in jener Zeit war g = 9807.48 mm

TSy = 0.5078344'~' 6 0 = 0.5077579SeC T,, = 0.5077119SeC . 1 = [9 003324 - 101 .g' T2 Nach

wo T in Sternzeit verstanden ist, wird daher

ls9 = 254.87 nim lg0 = 254.80 mm l,, = 254.75 mm . Endlich betragt das Gewicht der Miinchener Pendel in Granim

Bm,, = 1108 .5 BHZg-, = 1099 2 Bm,, = 1129.2 . 4. Aus den Gleichungen

S l Z V Z s I 2 m 3- a l 2 p s 2 ?lZ S 2 ? , 1 + a X p = I = l-+ AI

folgt B,u a R - I - A2 B m Al

s = -

und mithin, wenn man die Zahlen (2) bis ( 7 ) substituiert:

ssg = 231.13 rnm sgo = 2 3 1 . 1 7 mm

was gesucht war.

s,, = 231.40 mm

-

Nach den Erscheinungen, welche sich bei Pendel 89 gezeigt haben, und bei der theoretiscli erwiesenen grofien Bedeutung der Schneidenform mochte ich nicht empfehlen, die Deckplatte fest mit dem Wandstativ zu verbinden.

Es gibt ein vie1 einfacheres Mittel, die Deckplatte ,un- schadlich zu machen: man hebt sie nach jeder Pendelmessung ab. Dann verbindet sich die Art des Aufliegens mit den zufalligen Fehlern.

Am 30. November 1900 wurde das Pendel 89 beob- achtet, ohne dafi an der Deckplatte etwas geandert wurde:

The approximate position of this variable according to measures of two photographs taken with a 4.4-inch portrait lens is given above. I t lies in a region devoid of bright stars, and where there are many faint ones, but the adjoining little diagram will help in identifying it. The star marked a is BD. +32?3193 (9.2 mag.). The following results are based primarily upon 104 observations made with a 6'/,-inch reflector in the month of May of the present year, but the star is also shown upon 1 9 photographs obtained here. Upon most of these photographs the star is faint and only on one plate does it appear very bright. This circum- stance made i t . seem probable that the star belonged to that extreme type of short period variation which has been termed >Cluster-type< by Bailey and >Antalgol- type. by Hartwig ; and the observations soon showed in fact that it was an unusually exaggerated specimen of this type, the rise from minimum to maximum occurring in the short period of 6 I minutes, whilst the decrease takes I I rjrn, the ratio of increase to decrease being thus 0.09.

Beginn 9h15m 5078394"

1 0 45 8393 X I 30 8387

I 0 0 8386

1 2 I 5 8386

und am I . Dezember 1900 wurde nach jeder Messung nicht nur die Platte abgehoben, sondern auch die Schrauben wurden gelost und die Spitzenschrauben verstellt, dann die Platte neu aufgelegt und nivelliert. Dasselbe Pendel ergab :

Beginn 8h40m 5078393e

I 2 1 0 8394 I 5 5 8394 3 40 8392

10 2 5 8386

Der mittlere Fehler einer Messung betragt

dort: f 3 . 7 e hier: - ~ - 3 . 3 ~ .

Aus diesem Grunde habe ich wahrend der ganzen Expedition I 902 dieses Verfahren eingehalten, ohne daB irgend eine ungtinstige Wirkung bemerkt wurde.

B. Anding. ~

Miinchen, 1902 Dez. 25.

New Variable Star 19.1903 Lyme. RA. = 18~38~~1359, Decl. = +32D3g1~ (1855).

foll.

North

south

prec.

17

259 3880 2 60

Light- Star scale a 4 7 . 2 b 30.8 C 2 5 . 1

d 15.4 e J O . 0

T h e following light scale is based upon sequences of steps made on six nights with the reflector. T h e magnitudes in the last column have been derived by assuming the star a t o be 9.0 mag., and the value of a step to be 0.06 mag.

Mag.

9.00 9.98

E

709 '497 2 5 7 5

2 5 7 9 2 6 1 2 2614 2 6 1 6

2 6 2 2

I

T h e table below contains particulars of six observed maxima. Also, as already stated, the star is very bright on one photograph, taken on Nov. 2 , 1901, with a n exposure of 2gm, from gh57"' to 9h26m, and taking everything into account, it seems probable that the star must have been a t or very near its maximum brightness then. T h e middle of the exposure has consequently been assumed as the time of maximum. The table contains, besides the observed . .

10.33 10 .91 I 1 . 2 3

Date 1899 Sept. 28 1 9 0 0 B 25

1901 Nov. 2

.% 9 B 2 6

2 7 * 28 a 3 7

'903 May 7

Greenwich mean times of maximum, the computed times according to the elements given further on, and the residuals c - 0.

Cornp. Max. 0bs.Max. C-0 Weight.

1 2 ~ zm ( 1 2 ~ 3 7 " ' ) (-35") ph. 1 1 46 (12 5 2 ) ( - 66) Ph.

9 I 1 9 1 1 0 Ph. I 3 7 ' 3 '5 - 8 2

I 4 I 2 I4 ' 3 2

I 1 8 1 0 28" +40 * I I 1 4 1 I 1 4 1 0 5 I 2 I 3 1 2 7 + 6 I

7 3 5 ' 14 0 - 9 3

-

T h e adopted period of variation is based upon the last 7 results of the above table, but as the star is shown bright on another plate dated 1899 Sept. 28, this will afford a valuable check upon its accuracy. T h e variable is about a quarter of a magnitude fainter on this plate than it is on that of 1901 Nov. 2, so that we are probably safe in as- suming that the star was within an hour of maximum. As will be seen from the preceding table, the computed time of maximum precedes the middle time of the photograph by 35", wich is quite satisfactory. Also on another plate, dated 1900 Sept. 25, the star is moderately bright, and must certainly have been within two hours of maximum. H e r e also the residual of -66" is quite satisfactory, so

Period of variation Epoch of maximum

Maximum brightness 9.87 mag.

0 ~ 1 z ~ 1 6 ~ 1 5 B o = o d 5 1 1 2 8 4

1903May31, 1 3 ~ 5 1 " G r . m . t. = J. D. 2 4 1 6 2 6 6 d 5 7 6 8

Minimum brightness 11.23 b)

Minimum to maximum l h I m

Maximum to minimum I 1 I 5

Ratio of increase to decrease 0.09

T h e light curve of the present variable almost exactly resembles those of Y Lyrae and UY Cygni t, but is of a more exaggerated type. T h e following is an ephemeris for

that it is clear that the adopted period must b e the truth. T h e concluded elements are as stated

E I903 G. M. T. 2647 June 13 gh37" 2692 July 6 8 48 2 7 3 7 29 8 59 2 7 8 2 Aug. 2 1 9 1 0

2 8 2 7 Sept. 13 9 2 2

2872 Oct. 6 9 33

very near below. on each succeding night.

every 45th maximum. Maxima will occur 32.5 minutes later

E 1903 G. M. T. 2917 . OCt. 29 9h 44"' 2962 Nov. 2 1 9 5 5

I

3 0 0 7 - Dec. 14 10 6 I904

3 0 5 2 Jan. 6 1 0 18 3097 29 1 0 29

2 0 Hove Park Villas, Hove, 1903 June 8. A. Staizley Williams.

* A subsequent determination makes the time of maximum IIh3m. This would reduce this large residual to +5'". The rise to It should be mentioned that the correction for the equation maximum was not observed, so that the time is necessarily somewhat approrlmate.

of light has not been talcen into account, and that the observed times are geocentric times. t See Monthly Notices, Vol. 62, p. 206 and Vol. 63, p. 308.

Anzeige. An der Heidelberger Sternwarte (Astrom. Abt.) ist baldnioglichst die Stelle eines Assistenten durch einen Anmeldungen nimrnt Prof. Valenliner entgegen. jtingeren, aber im Beobachten nicht unerfahrenen .4stronomen zii besetzen.

I n h a l t zu Nr. 3879-80. E. Anding. Star 19. 1903 Lyrae. 257. - Anzeige. 259.

Uber die Bewegung eines Pendels auf geneigter Unterlage. 225. - A. Stanley WilZiums. New Variable

Geschlossen 1903 Juni 24. Herausgeber: H. K r e u t a . Druck von C. S c h a i d t . Expedition: K i d , Niemannsweg 10;