"I don't take to {slaves} off the plantation. This way they don't know which way is east, which way it is to the west. Once they have figured where someplace else is -- next thing you know, they'll know which way it is to the north." So says "Mr. Ames," a slave overseer in the television version of the novel "Roots" by Alex Haley. The line illustrates vividly the desperate measures used by slave owners to reduce the number of escapees in the decades before the Civil War. Often the effort was futile. Slaves knew well that freedom lay to the north, and though their owners and overseers never would guess it, slaves knew precisely how to locate certain groups of stars in the night sky that pointed the way north as surely as a compass. But they kept that knowledge, like so many other aspects of their lives, well concealed from owners. For many held in bondage in Alabama and Mississippi, clues in the sky and other directions on how to reach the North, were camouflaged in a remarkable folk song called "Follow the Drinking Gourd." Though well-known in those states, the song lapsed into obscurity after Emancipation until it was rediscovered in this century and its hidden meaning revealed. In 1912, in North Carolina, an amateur folklorist named H.B. Parks accidentally overheard an African American man singing a folk song new to Parks, for whom the words made no sense. When Parks asked about it, he was refused an explanation. A year later, he heard the song again, in Louisville. Again the singer declined to explain the curious lyrics. Sometime after 1918, Parks finally met a black man in Texas who was willing to explain it. Senseless as they seemed, the lyrics gave slaves directions for using the pattern of stars in the night sky and blazes marked on riverside trees to find their way north. The song, Parks wrote in an obscure journal, "Publications of the Texas Folklore Society," was taught to slaves by an itinerant carpenter named Peg Leg Joe. Parks suspected that Joe, probably a white man, had been connected with the Underground Railroad -- the whimsically named network of whites, mainly in the North, who hid escaped slaves from bounty hunters and helped them to travel farther from the South toward new lives in the North or even in Canada. Some of Parks's information about the song came from his interviews with people involved with the Underground Railroad. Joe, they told Parks, arrived in the South each winter, moved from one plantation to another teaching the song, and left in the spring. Afterward, slaves from areas where he had worked began fleeing north. Parks's article, and perhaps the song itself, might well have been forgotten had a more prominent folklorist, B. A. Botkin, not found Parks's article and essentially repeated it in his 1944 book, "A Treasury of Southern Folklore." The words of the song and the interpretation are: When the sun comes back, And the first quail calls, Follow the Drinking Gourd. For the old man is a'waiting for to carry you to freedom If you follow the Drinking Gourd. The words instruct slaves to begin the trip north in late winter or early spring. "When the sun comes back" signifies the time after the winter solstice, usually around Dec. 21, when the altitude of the sun at noon is higher each succeeding day. Migratory quail spend the winter in the southern states and begin calling in early spring. The Drinking Gourd is the Big Dipper, the constellation of seven stars that is always in the northern sky. "Follow the Drinking Gourd" means to walk toward the constellation. The "old man" is Peg Leg Joe. The river bank makes a very good road, The dead trees will show you the way. Left foot, peg foot, traveling on, Follow the Drinking Gourd. This verse instructs the escapee to travel north along the bank of the Tombigbee River, which reaches from the Gulf Coast of Alabama to northern Mississippi. Dead trees along the bank would bear the markings, sketched in charcoal or mud, of a left foot and a peg foot. The river ends between two hills, Follow the Drinking Gourd. There's another river on the other side, Follow the Drinking Gourd. The third verse instructs slaves to go north between the hills to the Tennessee River and follow it north. The Tennessee winds north across Tennessee and Kentucky and empties into the Ohio River. When the great big river meets the little river, Follow the Drinking Gourd. For the old man is a'waiting for to carry you to freedom If you follow the Drinking Gourd. The final verse instructs the escapees to continue north, even after the "great big river," the Ohio, meets the narrower Tennessee. On the north bank of the Ohio at that point was Illinois, a free state. There somebody waited to escort them into the better organized part of the railroad. By 1831, the Underground Railroad comprised a well-organized network of antislavery whites in northern states and was turning its attention to working in the South. Members knew slaves were aware of the Big Dipper and the North Star to which the dipper points, but slaves were kept so ignorant of geography that they could not plan a route. So railroad workers began traveling into the South to function as guides or to provide route instructions. In addition to the Drinking Gourd song, several others have become known as pertaining to details of geography in other parts of the South. By the beginning of the Civil War in 1861, an estimated 500 people were in the South each year to provide route instructions, and well-established "lines" out of the South were in use. An estimated 60,000 to 100,000 slaves found their way to freedom via the Underground Railroad over the decades of its operation.

So much secrecy surrounded the railroad's activities in the South that very little is known of them. "Follow the Drinking Gourd" is the only known description of an entire route. Markings on the trees distinguished the Tombigbee from other rivers that run north to south and also may have provided guidance on the overland route from the Tombigbee to the Tennessee. Escapees had to cross the Ohio River, which is too wide and swift for most swimmers. Boats could come from the Illinois side to pick up travelers, but bounty hunters routinely prowled the south bank where it would have been unwise to spend too much time waiting. If a person reached the Ohio in winter, however, the river often was frozen over and could be crossed on foot without delay. This is, apparently, what usually happened. The straight-line distance between Mobile, Ala., at the mouth of the Tombigbee and the confluence of the Ohio and Tennessee Rivers is about 800 miles. Traveling the winding routes of the rivers may have doubled that, so slaves from the Deep South often needed a year to reach the Ohio. The railroad instructed slaves to leave the previous winter to provide such travel time. Between 160,000 and 200,000 slaves lived near the Tombigbee. Thus, the "line" served a large population, with the rivers acting as natural highways and the route terminating close to the start of several main railroad lines in the North. Many authorities believe that slaves created the drinking gourd song. Before the advent of writing, African tribal life routinely used song to store and convey information. Slaves carried that tradition to America and created many songs that relayed information they wanted to keep from whites, who could not interpret codes they did not know existed. The songs rely on the technique of masked language, which uses words that seem innocuous but communicate vital information to those aware of the secret. "Follow the Drinking Gourd" masks instructions for finding the North Star, or Polaris. Located almost directly above the Earth's North Pole, this star is a better indicator of true north than the best compass. All other stars appear to shift in the sky because of Earth's daily rotation on its axis and its yearly trip around the sun. Polaris, in its unique position, is unaffected by these motions and always points due north. But the North Star is so dim, that even experienced sky watchers need help finding it. The seven brilliant stars of the Big Dipper serve this purpose. Beginning at the tip of the dipper's handle, observers count through the stars of the Dipper until they reach the two stars at the end of the Dipper's bowl. Mentally, a line is drawn from the star at the bottom of the bowl to the star marking the top of bowl. This line is continued across the sky until it touches the next star, Polaris. The song uses the gourd rather than Polaris because slaves would not have created a song that openly used common names of the stars or constellations. As children, historical sources confirm, slaves learned the significance of Polaris and how to locate it. Because both Polaris and freedom were to the north, Polaris came to symbolize freedom and slaves couched many other references to freedom in terms of a star. The railroad adopted that language. Frederick Douglass, an ex-slave and prominent journalist, called his pioneering abolitionist newspaper "The North Star." Gloria D. Rall is on the staff of the New Jersey State Planetarium in Trenton.

Follow Even Further: * To see a free planetarium show for children on the Drinking Gourd, go to the Air and Space Museum on Saturday, Feb. 18. At 10 a.m. the museum's Einstein Planetarium will present a program based on Jeanette Winter's book of the same title. * To read more about the Drinking Gourd and the Underground Railroad, look for these books and magazines: "A Treasury of Southern Folklore" by B.A. Botkin, Crown Publishers, 1944. The first prominent treatment of "Follow the Drinking Gourd." "Hippocrene Guide to the Underground Railroad" by Charles L. Blockson, Hippocrene Books, 1994. Lists all known railroad sites and contains other code songs. "Escape From Slavery: The Underground Railroad" in National Geographic magazine, July 1984. Explains the railroad and the astronomical aspects of Polaris. "Follow the Drinking Gourd" by Jeanette Winter. Alfred A. Knopf, 1988. An excellent children's book using a fictional slave family to show how the song worked. CAPTION: The "Drinking Gourd," or Big Dipper, points to Polaris, the North star. Using this orientation of the stars as a guide, one could travel north toward the "free states" without much other guidance.