b'the hot spot built volcanoes that eventually grew above sea level to form (the Hawaiian) islands. But because the seafloor on which they were built was continually moving northwestward across the hot spot at a rate of 7-9 centimeters per year, eventually each volcano was torn away from the hot spot and carried northwestward, just as a conveyor belt moves material from one location to another. Such is the (eventual) fate for the active volca-noes on the Big Island, though they will be replaced by new volcanoes.A L A N G U A G E A L L T H E I R O W NVolcanoes have their own language and here in Hawai`i, even their own goddess. Visitors are sure to hear stories of Pele, the fire goddess of volcanoes; discover the difference between `a` (sharp, brown) and phoehoe (smooth, black) lava; drive past cinder cones and pu`u formations; and view spatter ramparts, lava tubes and caves, and crustal overturn-ings by the side of the highway. Why so much variation in the look and texture of our lava fields? All Hawaiian lava is black when it first cools but may turn more brownish as the iron in the lava oxidizes with rain and time, says James Kauahikaua, a geophysicist with the USGS Hawaiian Volcano Observatory. The type of lava`a` or phoehoeis the result of sheer stresses within the liquid lava while it is flowing. Higher eruption rates characteristic of the early days of an eruption usually produce `a` lava, whereas lower eruption rates usually produce phoehoe lava. There is no substantial difference in chemistry between the two forms of lava.The early Hawaiians made creative use of the dominant material they had on hand, using the lava rock to build boundary fences, pens for livestock, heiau (religious plat-forms), and fishpond seawalls among many things.5 5'