It is like visiting the houses at Pompeii, to enter the strange little black warehouses which cover some of our smaller wharves. They are so old and so small it seems as if some race of pygmies must have built them. Though they are two or three stories high, with steep gambrel-roofs, and heavily timbered, their rooms are yet so low that a man six feet high can hardly stand upright beneath the great cross-beams. There is a row of these structures, for instance, described on a map of 1762 as "the old buildings on Lopez' Wharf," and to these another century has probably brought very little change. Lopez was a Portuguese Jew, who came to this place, with several hundred others, after the Lisbon earthquake of 1755. He is said to have owned eighty square-rigged vessels in this port, from which not one such craft now sails. His little counting-room is in the second storey of the building; its wall-timbers are of oak, and are still sound; the few remaining planks are grained to resemble rosewood and mahogany; the fragments of wall-paper are of English make. In the cross-beam, just above your head, are the pigeon-holesonce devoted to different vessels, whose names are still recorded above them on faded paper,--"Ship Cleopatra," "Brig Juno," and the like. Many of these vessels measured less than two hundred tons, and it seems as if their owner had built his ships to match the size of his counting-room. A sterner tradition clings around an old building on a remoter wharf; for men have but lately died who had seen slaves pass within its doors for confinement. The wharf in those days appertained to a distillery, an establishment then constantly connected with the slave-trade, rum being sent to Africa, and human beings brought back. Occasionally a cargo was landed here, instead of being sent to the West Indies or to South Carolina, and this building was fitted up for their temporary quarters. It is but some twenty-five feet square, and must be less than thirty feet in height, yet it is divided into three stories, of which the lowest was used for other purposes, and the two upper were reserved for slaves. There are still to be seen the barred partitions and latticed door, making half the second floor into a sort of cage, while the agent's room appears to have occupied the other half. A similar latticed door--just such as I have seen in Southern slave-pens--secures the foot of the upper stairway. The whole small attic constitutes a single room, with a couple of windows, and two additional breathing-holes, two feet square, opening on the yard. It makes one sick to think of the poor creatures who may once have gripped those bars with their hands, or have glared with eager eyes between them; and it makes me recall with delight the day when I once wrenched away the stocks and chains from the floor of a pen like this, on the St. Mary's River in Florida. It is almost forty years since this distillery became a mill, and sixty since the slave-trade was abolished.