In 1611–12, the Admiralty of Amsterdam sent two covert expeditions to find a passage to China with the yachts "Craen" and "Vos", captained by Jan Cornelisz Mey and Symon Willemsz Cat respectively. Adriaen Block, Hendrick Christiaensen, and Cornelius Jacobsen Mey explored, surveyed, and mapped the area between Maryland and Massachusetts in four voyages made between 1611 and 1614. These surveys and charts were consolidated in Block's map, which used the name "New Netherland" for the first time; it was also called "Nova Belgica" on maps. During this period, there was some trading with the Indian population.