Saraswati ParkA tremendous first novel from an exciting young author. Feted for its electric chaos, the city of Bombay also accommodates pockets of calm. In one such enclave, Mohan, a middle aged letter writer the last of a dying profession sits under a banyan tree in Fort, furnishing missives for village migrants, disenchanted lovers, and when pickings are slim, filling in money order forms. But Mohan's true passion is collecting second hand books; he's