Here, season by season, are some of the things you might be doing to live a little more freely, a little more fully, a little more in touch with the natural world. In spring, watch the birds return, go canoeing (not difficult on flat water and not dangerous), hunt rocks, walk (abandoned railroads, dirt roads, towpaths suggested); come summer, get a horse, build a raft or ride an inner tube, gather mussels or collect shells. Fall is ideal for orienteering and the only time to gather nuts; among winter's uncommon pleasures are tracking (plus stalking, to get close) and skate-sailing--but going for a walk in the snow can be its own reward. (The author once got happily lost in New York's Central Park.) An informal essay describes each activity in such a way as to encourage and reassure the neophyte--and de-emphasize equipment and techniques. Appended are sources of further information, including field guides and lists of locales and local associations. John McPhee readers, especially, take note.