India, June 6 -- Washed laundry is drying in the porch. The bungalow truly looks ordinary, here in Gurugram's Sector 14. A jaali door opens into a corridor illumined in the afternoon light. Spotting the staircase inside gives the first jolt. It is littered with neat stacks of books. Up the stairs, the veranda is wholly crammed with books. So is the drawing room. So are the two bedrooms. The kitchen, too. Books claim beds, sofas, tables and chairs.

This private library is the work of a lifetime.

At 84, the antiquarian bookseller Vijay Kumar Jain is warming up to the theme of retirement. His long relationship with "old, rare books on South Asia in general and India in particular" had begun in the 1960s. Gradually, the collection became re...