Dee attended Chelmsford Chantry School (now King Edward VI Grammar School) in 1535–1542. He entered St John's College, Cambridge in November 1542, aged 15, graduating BA in 1545 or early 1546. His abilities recognised, he became an original fellow of Trinity College, Cambridge on its foundation by Henry VIII in 1546. At Trinity, the clever stage effects he produced for a production of Aristophanes' "Peace" earned him lasting repute as a magician. In the late 1540s and early 1550s, he travelled in Europe, studying at Louvain (1548) and Brussels and lecturing in Paris on Euclid. He studied under Gemma Frisius and became friends with the cartographers Gerardus Mercator and Abraham Ortelius. Dee also met, worked and learnt from other continental mathematicians, such as Federico Commandino in Italy. He returned to England with a major collection of mathematical and astronomical instruments. In 1552, he met Gerolamo Cardano in London, with whom he investigated a purported perpetual motion machine and a gem supposed to have magical properties.