Photoelectric observations of Magellanic Cloud cepheids

This is a brief account of some photoelectric observations of Magellanic Cloud cepheids, begun in 1951 with Dr. G. E. Kron on the 30-inch reflector, and since continued there and on the 50- and 74-inch reflectors. The initial emphasis was on colour, the Cloud cepheids, as measured, being considerably bluer than those in the Galaxy. It is now known that this discrepancy is due mostly to reddening of the galactic cepheids, and interest has shifted rather to the differences in the period-luminosity relations in the two Clouds, as revealed by measurements made in the SMC by Arp (1960), and in the LMC by Woolley et al. (1962).