Catherine Gehrig, the heroine of Peter Carey’s new novel, The Chemistry of Tears, is a museum conservator and a horologist, which is to say that her life is dedicated to precision, and good order, and the restoration of the chaotic damage inflicted by time and human carelessness. One day she arrives for work at the Swinburne Museum, one of those jewel-like, hidden treasure houses with which London is so fortunately endowed, to learn that her colleague, Matthew Tindall, is dead. He suffered a catastrophic heart attack on the Tube. Matthew was Catherine’s lover for 13 years, a fact unknown to any of her colleagues except Eric Croft, the head curator of horology, who loved them both.