Like the two hemispheres of the world it considers, public television’s “The Explorers: A Century of Discovery” (tonight at 8 p.m. on Channel 50 and at 9 p.m. on Channels 28, 15 and 24) is neatly divided in half--all ready, it would seem, for future pledge-break use.
The first half is an engrossing history of the National Geographic Society, whose 100th anniversary this 90-minute compendium celebrates. The second half is made up of short sequences from relatively recent Geographic TV specials.
And even though the second half would seem to hold the more interesting sights--color film of the discovery of the Titanic’s wreck, of Jane Goodall, of Dian Fossey (the subject of the new movie “Gorillas in the Mist”), and so on--its diffuse, scattered effect suffers in comparison to the collection of more rarely seen black-and-white footage and often fascinating history in the preceding 45 minutes.
In the historic part we see the polar expeditions of Robert Peary (north) and Richard Byrd (south); the “Valley of 10,000 Smokes,” a temporary steam-fissure phenomenon caused by volcanic conditions in the Alaska of 1917; early, daring bathysphere dives and balloon ascents; and much more.
That “more” contains a bit more about the Bells and the Grosvenors (the founders and leaders of the National Geographic Society) than anyone outside the family might like to know. But “The Explorers,” even with its shortcomings, proves rewarding viewing.