It so happens that London during all the centuries of its growth, and especially during those four hundred years of the Middle Ages which chiefly established its great position, was in exactly this position. Not only was it, as modern Liverpool is, a point of transhipment round which a vast quantity of subsidiary activities had grown, it was also close to the more or less permanent residence of the court, to what became the permanent seat of legislature, and to what was very early the permanent seat of the central courts of justice. The process continued uninterruptedly. After the loot of the church land of the endowments of the poor under the Tudors, the great palaces of the new aristocracy lined the Strand, and from the early seventeenth century--when this process was completed--onwards, the power of demand exercised by London alone and its local call for imports, has never ceased to grow, until to-day the position of London as an importing centre is due almost entirely to this character, next to its value as a clearing house: It is now only in a much less degree a point of transhipment. The type of goods for which this local power of demand existed had also a very great effect in helping the growth of London through the traffic of the Thames. Perhaps the principal import of the Middle Ages in value was that of wine. It was a luxurious import for which there was a local demand, especially where you had the residence of the wealthier people, and, what was exceedingly important, it was _an import large in bulk_. It meant that ships would come either in great numbers or in heavy tonnage, and this in itself suggested London as a place of export for their return, made a speculative voyage to London worth taking, and developed the warehousing space and the wharf space of the port. Later came coal, later still the tropical products, and last of all the great passenger traffic. But in every stage of the development London has exercised a local power of demand for that kind of import which demanded bulk in storage.