Neverglade was an astronomer who spent some time on Traken. He was accompanied by his companion, Viola.
Neverglade's project was a scale model of the universe. He worked in a large, spherical observatory. He used books and telepathic equipment to create his model. He was assisted by the Second Doctor, who was also visiting Traken with Jamie McCrimmon and Victoria Waterfield.
Neverglade's model universe adversely affected the biomatrix of Traken, causing the people to behave strangely and the Melkur to come to life. Neverglade and his companion were asked to leave Traken by Consul Symia.
In reality, Neverglade was an illusion conjured up by Viola as a means of travelling the universe. (PROSE: The Astronomer's Apprentice)