Twenty Years ago, in a souvenir article on revolutionaries, I wrote: “The revolutionaries whose story I propose to relate covered a whole gamut, ranging from raw terrorists to sophisticated Marxists.” This book is an attempt to study the movement and its impact in greater details. The movement itself had a tortuous and uneven course, resembling the progress of a river: sometimes it was just a shred of water and at other times it was a flood with its eddies and undercurrents.