COMMISSION 27 OF THE I. A. U. INFORMATION BULLETIN ON VARIABLE STARS NUMBER 204 Konkoly Observatory Budapest 22 May 1967 PRELIMINARY RESULTS OF PHOTOELECTRIC OBSERVATIONS OF RU CAM The observations were made with a 30 cm-reflector, from Dec. 1966 until April 1967. They fit well Wamsteker's ones of Sept. 1965-Febr. 1966 (IBVS 128, 1966) both in phase and in range of the variation, adopting V=9.08 for his comparison star. The mean error in magnitude and in colour, obtained from separate reduction of the data of the comparison stars, are of the order of 0.01 magnitudes. In the Table, Phase=(J.D. -2439000). P^-1 with P=22.^d134; n=number of individual observations of the variable star. [FIGURE 1] J. D. 2439000+ Phase V B-V n 481.604 .759 8.509 +1.142 10 494.431 .338 8.578: 1.187: 3 495.375 .381 8.606 1.190 9 503.376 .742 8.541 1.180 7 504.330 .785 8.547: 1.172: 3 506.348 .876 8.546: 1.172: 6 508.500 .974 8.529 1.180: 3 529.385 .917 8.517 1.186 7 531.400 .008 8.547 1.187 9 532.325 .050 8.547 1.194 8 533.333 .096 8.552 1.209 12 537.330 .276 8.623 1.224 11 562.375 .408 8.565: 1.175: 1 564.375 .498 8.570 1.161 8 564.375 .498 8.556 1.162 8 565.356 .542 8.549 1.137 9 565.356 .542 8.542 1.141 9 568.385 .679 8.482 1.128 5 568.385 .679 8.483 1.129 5 572.330 .858 8.48 1.18 6 597.346 .988 8.52 1.21 3 598.355 .033 8.542: 1.20 7 600.375 .125 8.618 1.200 11 601.362 .169 8.62 1.195: 2 604.344 .304 8.601 1.203 10 Compar. V B-V star +70d448 9.09 +1.09 +69d442 8.04 +0.80 +70d447 9.08 +0.31 +69d420 8.92 +0.51 Trieste Observatory May, 1967. B. CESTER NOTE ON RU CAMELOPARDALIS We began the observation of RU Cam in the summer of 1966 with the aid of the UBV photometer on the 24" reflector. Since August 10 the variable star was observed for a total of 149 nights, together with the comparison star BD +70d448. The time interval between two successive light minima fluctuated in the 13 cycles observed by us between 20.^d5 and 24.^d2 around a mean cycle length of 21.^d8. At the beginning the amplitude in V was about. 0.^m10, later it decreased to 0.^m07, reaching its minimum value in November 1966. Since then the amplitude was increasing slowly, and after some fluctuations it reached the value 0.^m20. Simultaneously the amplitude in B-V increased from 0.^m04 to 0.^m11. Also the median brightness of the different cycles was liable to fluctuations amounting to 0.^m06. Chester's observations published above are in accord with ours. Supplementary observational material is needed for the following time intervals: J.D. 2439427-438, 440-454, 472-476, 494-501, 548-553, 625-635. The observed amplitude-increase seems to be in agreement with our prediction in IBVS 152, p. 4, still we intend to continue the observation of the star. Konkoly Observatory, Budapest L. DETRE B. SZEIDL NEW VARIABLE STARS IN HERCULES On plates taken with the 24-inch Schmidt telescope three new variable stars with large amplitude were found. RA (1950) D Max Min Type J1 18^h16^m55^s +22d06.'1 15.^m0 >19^m Mira J2 18 17 36 +22 32.9 13.4 >19 Mira? J3 18 21 57 +23 36.0 16.1 >19 ? In the column "Max" the brightest observed magnitudes in B-colour are given. In minimum, the stars are fainter than our plate limit. On the copies of the Palomar Sky Survey J1 is red, spectral type K. At the following dates, the stars appeared bright: J1: J.D. 2434896 (Palomar Sky Survey) J2: 2439266 8642 J3: 2438583 9299 8642 9557 9299 [FIGURE 2] 1. BD +22 3336 2. BD +23 3325 3. BD +22 3335 University Observatory, Jena S. HANFT