Fairfax House, York, is holding an exhibition, Keeping Time. This exhibition focuses on and celebrates the excellence and innovation of clock and scientific instrument makers from Yorkshire. Centrepiece of the exhibition is the John Harrison precision pendulum clock No. 2, on which Harrison began his precision timekeeping research in response to the Longitude Act of 1714. Harrison's research eventually led to the practical solution to determining longitude. Not knowing one's longitude was a major navigational problem, and had often spelt disaster for mariners, either getting lost, or running into obstacles, running out of sea room, and ending up on lee shores. This Harrison clock has been written about in earlier blogs, under History of Science. Loaned from Leeds Museums and Galleries, the exhibition opens on 5 October, 2012 and runs through to the end of December. Following on from suggestions from LMG staff, Fairfax House has also borrowed the Harrison brothers sundial made for Holy Trinity Church, Barrow-upon-Humber, and the highly signficant equatorially mounted telescope, made by Henry Hindley of York, and which is part of the scientific instruments and specimens collection at Burton Constable Hall.