For help with details of fact and language, for assistance in tracking down materials, and for their support, I am greatly beholden to Robert Antony, Pengyew Chin, Amar Farooqui, Atish Ghosh, Guoliang Guo, Ashutosh Kumar, Jiajing Liu, Ming Lu, Megha Majumdar, Cecil Pinto, Rahul Srivastava, Mo-lin Yee, Xu Xi and most particularly, Kingsley Bolton and Robert McCabe. To Shernaz Italia, Freny Khodaiji and their extended families, I owe an immense and very special debt of gratitude.

The long journey upriver would have been vastly more difficult without the unflagging support of Barney Karpfinger, my agent, and Roland Philipps, my publisher and editor in the UK; without Debbie, my wife and first reader, this vessel would almost certainly have run aground; without my children, Lila and Nayan it could not have kept to its course. My mother, Anjali Ghosh, taught me to read – without her the voyage would never have begun.