Abstract. Elemental abundances analyses are performed for the Mercury-Manganese stars υ Her, φ Her, and HR 7018 consistent with previous studies of this series using spectrograms obtained with Reticon and CCD detectors. Comparisons of the first two analyses with those performed using coadded photographic plates show the general consistency of the derived elemental abundances. For υ Her and for φ Her, abundances were newly found for O, and for Al, V, Zn, and Ce, respectively. HR 7018 is discovered to be a single-lined spectroscopic binary. Its Sc abundance is the smallest of any class member with derived abundances and its Sr abundance the largest of any known HgMn star. A correlation analysis of the most complete abundance sets for 20 HgMn stars shows that the abundances of some elements are correlated with one another and some are functions of the stellar effective temperature.

Abstract. Effective temperatures and surface gravities for 48 main sequence band B and A stars were found by matching optical region spectrophotometry and Hγ profiles with the predictions of ATLAS9 solar composition model atmospheres. When these values were compared with those found using Strömgren uvbyβ photometry based on ATLAS6 model atmospheres, we found a difference (photometry-spectrophotometry) of 25±118 K for 29 stars with 8000 K ≤ T eff ≤ 10 050 K compared to 76 ± 105 K for 14 stars with 10 050 K ≤ T eff ≤ 17 000 K. The surface gravity scales are in agreement. These stars are sufficiently hot that their effective temperatures and surface gravity determinations are unaffected by discrepancies due to the choice of Mixing-Length or Canuto-Mazzitelli convection theories.

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Abstract. Differential Strömgren uvby photometric observations from the Four College Automated Photoelectric Telescope are presented for the ellipsoidal variable 33 Tauri, and the magnetic Chemically Peculiar stars HD 50169 and HR 7786. We confirm that Hube's period of 2.975272 days for 33 Tau is correct. HD 50169 is a constant MCP star. HR 7786 is a large amplitude class member confirming Winzer's discovery, but its period is 8.5297 days. Its comparison star, HR 7721, a spectroscopic binary B7 V star, is variable with an amplitude of order 0.1 mag, but of indeterminant period. In addition Hipparcos photometry of the comparison and check stars for early type stars whose photometry is being obtained with the FCAPT is reviewed to ascertain the stability of these stars.