In this attractive and unusual map, the counties of Middlesex and Hertfordshire are shown together and oriented with north to the right of the plate. Jan Jansson Jr (1588-1664) was the son of a bookseller and publisher who had worked with Jodocus Hondius Sr. From about 1633 onwards, his imprint appears on the title-pages of the Mercator-Hondius “Atlas”, in conjunction with his brother-in-law, Henry, as they re-issued their “Atlas” in competition with the Blaeus. At this time, many of the maps were re-drawn or replaced and the “Atlas” was expanded to become the “Atlas Novus” series, an attempt to rival Blaeu’s “Atlas Maior” for size and quality. Jansson began to prepare his volume devoted to the British Isles c.1640. In 1644 he published eleven county maps in an appendix to the “Atlas”, but they appeared from 1646 in the “Novus Atlas”. Jansson’s county maps are seen far less frequently than those of his rival Blaeu, but are similar in appearance with coats of arms and decorative title cartouches. Jansson, like Blaeu, used Speed maps when creating his own thus showing hundreds but no roads. However, Jansson (and Blaeu) chose to omit Speed’si nnovative town plans. This example is a re-issue by the noted Amsterdam map publishers, Schenk and Valk.