At the beginning of the seventeenth century the established posts were only four in number,--the post to Scotland, the post to Ireland, the post to Plymouth, and the post to Dover; and of these the most important by far, because the most used, was the last, the post through the county of Kent. It was through this county that the high-road to the Continent lay, and, while commercial relations as between one town and another within the kingdom were yet a thing of the future, the foreign trade of the country had already reached very considerable proportions. The persecutions in France and the Low Countries had driven a large number of foreigners to London, and here the Flemings introduced the manufacture of wool into cloth. In this commodity alone the exports from England to the Netherlands in the time of Philip the Second amounted to five millions of crowns annually.[4] In education no less than manufactures the Flemings were far in advance of our own countrymen. There was scarcely a peasant among them that could not both read and write. While, therefore, the other three posts of the kingdom were still being little used except for letters on affairs of State, the post to the Continent had already become matter of public concern. [4] An amusing illustration of the value which, at the end of the sixteenth century, was set upon cloth made in London is afforded by a letter from Frederick the Second of Denmark to Queen Elizabeth. This letter, dated the 14th of June 1585, is thus summarised in the 46th Annual Report of the Deputy-Keeper of the Public Records, Appendix ii., page 28: "Has for some years past had cloth prepared in London of different colours and after a particular pattern, for his use in hunting both in summer and winter. Hears now that certain German merchants, having found this out, have had similar cloth manufactured, which they sell everywhere, outside his Court and family, to many inquisitive and foolish imitators, at a very dear rate. It is no concern of his what anybody may wear, but still, as this cloth was made of a special kind and colour for himself, he takes it ill that it should be sold to others, and begs her therefore (on the application of his agent, Thomas Thenneker) strictly to prohibit the sale."