sentences:  The third era, 1850 to 1860, was a brief interlude jumping to the East Coast, annexing the region from the Amur River to Manchuria.The fourth era, 1865 to 1885 incorporated Turkestan, and the northern approaches to India, sparking British fears of a threat to India in The Great Game.European colonization of both Eastern and Western Hemispheres has its roots in Portuguese exploration.