Victor Hugo's eponymous story entitled "Les Miserables" was first published in 1845. Your printing of the novel was actually done in installments in the magazine Seaside Library that was published by George Munro. The installments are bound together in one covered 'book'; this is referred to as 'bound periodicals'. Seaside Library magazine was established in 1877, whose first success was with The Fireside Companion magazine in 1867. The magazines specialized in printing fiction stories. Your first installment appears to be dated 1878. The estimate is based on actual recent past recorded auction sales of comparables.