Published in 1879, this Latin dissertation was the first substantial work on Archimedes by the Danish philologist and historian Johan Ludvig Heiberg (1854–1928), who the following year embarked on editing the three-volume Archimedis Opera Omnia (also reissued in this series). Much later, in 1906, he discovered a palimpsest containing previously unknown works by the Greek mathematician. The Quaestiones includes chapters on the life of the famous scientist of Syracuse, a discussion of his works and explanations of his mathematical and scientific ideas, as well as a survey of the extant codices known to the author. It also contains the Greek text, edited and annotated by Heiberg, of Archimedes' Psammites (The Sand Reckoner), a mathematical enquiry into how many grains of sand would fit in the universe. This includes mention of a heliocentric solar system, speculation about the size of the Earth, and Archimedes' other views on astronomy.