National Geographic May 1989

Searching for the Secrets of Gravity
The force that keeps our planet circling the sun and our feet on the ground is not as simple as Newton thought. Another force may be at work as well, reports John Boslough. Photos by James A. Sugar.
U. S. History in a Box { Introduction }
On April 30 National Geographic EXPLORER will televise the opening of a Long Island family’s time capsule, sealed a century ago. Space- age technology previews the contents, mementos of President Benjamin Harrison’s inaugural in 1889 and possibly of Ge
Are the Swiss Forests in Peril?
For centuries forests have sheltered Swiss valleys from avalanches. Today many trees, weakened by air pollution, insects, and former forestry practices, show alarming damage. Christian Mehr tells of efforts to save the forests. Photos by the author and;
Braving the Northwest Passage
For centuries European seamen tried to reach the Far East through the icy waters of northern Canada. Not until the early 1900s was the voyage made, and not until last August was it made under sail and muscle power alone. Jeff MacInnis and photographer Mi
Tepuis- -Venezuela’s Islands in Time { Venezuela’s Islands in Time}
Like fortresses in the clouds, lofty mesas called tepuis tower above forests edging the Amazon Basin. Author- photographer Uwe George visits the region that inspired Sir Arthur Conan Doyle’s Lost World, where unique plants and animals have remained all
The Baltic: Arena of Power
The rules have changed in this traditional East- West buffer zone, with glasnost and perestroika replacing hostility and suspicion. Priit J. Vesilind and photographer Cotton Coulson find the seven Baltic nations cooperating to save the sea they share.