Seminars will be held on Wednesdays at 5 p.m. in the Education Room of the Museum of the History of Science, Broad Street, Oxford, as follows: 25 April Thad Parsons III (University of Oxford) 'Many Failures: a Planetarium for London' 2 May Professor David Gooding (University of Bath) 'Visual Theories: Materials, Models and Methods' 9 May Dr Stephen Johnston (Museum of the History of Science) 'The Needle and the Dial: Thomas Digges on Magnetism as Mathematics' 16 May Professor Michael Cooper (University College London) 'Land Surveying: Millennia of Practice, but no History. Why?' 30 May Dr Gloria Clifton (National Maritime Museum) 'Planning the New Astronomy Galleries at Greenwich' To find the room, come down the outside stone staircase to the basement level and though the glass doors beneath Broad Street. All welcome.