A copy of Porter's script for 'The Night Sky in September' on prediction in astronomy; the Dublin meeting of the International Astronomical Union; the Square of Pegasus in the east with Delphinus, Capricornus, Aquarius, Pisces and Cetus; Hydra, Virgo and Ursa Major (examples of large constellations), the regularisation of the boundaries of all constellations in 1930, and Bayer's star atlas of 1603; Mira in Cetus, first mentioned by Fabricius in 1590, which Bayer entered on his 1603 atlas; Holwarda showing Mira to be a variable star in 1638, and Hevelius describing it in 1658; Mira's cycle of 333 days and photographic analysis showing that the total radiation output over the whole spectrum is not as great as expected; Mira, a red giant star, and direct interferometric measurement showing that the Earth in its orbit would fit inside Mira if it was where the Sun is; Mira having a companion star - a white dwarf; and theories of 'pulsating stars'.