He announced in 1844 the binary character of Sirius and Procyon from their disturbed proper motions; and was preparing to attack the problem solved later by the discovery of Neptune, when fatal illness intervened.
In the same author's Works and Days, a treatise which is a sort of shepherd's calendar, there are distinct references to the Pleiades, Hyades, Orion, Sirius and Arcturus.
The group consisting of five stars of Ursa Major together with Sirius has already been alluded to; another very marked group of 16 stars in Perseus, all of the Helium type of spectrum, form a similar association.
Coins of Ceos exhibit the head of Aristaeus and Sirius in the form of a dog crowned with rays.
From comparisons between the observed places of Arcturus, Aldebaran and Sirius and the places assigned to them by Alexandrian astronomers, he was led to the opinion that all three are moving towards the south (Phil.
In this case the companion, being about half the mass of Sirius itself, has probably cooled more rapidly, and on that account emits much less light.