If the Negro slaves were not able to physically escape their confinement, which most of them were unable to do, they would often escape emotionally by singing. These songs, known as Negro spirituals, served many purposes for the slaves.
First, some of the Negro spirituals included directions and warnings for those who were traveling via the Underground Railroad. If the singers themselves could not escape, at least they could help others do so. One example is "Follow the Drinking Gourd," which includes these lines:
The riverbank makes a very good road.
The dead trees will show you the way.
Second, these spirituals provided comfort to the slaves who had nothing here on earth to look forward to but a continued life of misery. They often sang about a future in heaven in which there would be joy and where they would be reunited with their loved ones--not an insignificant hope to a slave.
Finally, singing these songs served to mask their hopelessness and anger about being slaves. While virtually nothing about their circumstances offered the slaves any hope that their suffering would be lessened, slave owners could often be fooled into thinking the slaves were content. This may have served the dual purpose of preventing worse treatment and allowing the slaves to express their sorrows and anger without being punished for it.
While a physical escape from slavery would have been every enslaved black person's first choice, they usually had to settle for emotional escapes, such as those provided by singing Negro spirituals.
Open acts of rebellion and of escape by slaves in the Antebellum Era was the rarest of all incidents of defiance against being held against someones own will. Slaves acted out against the "peculiar" institution, as historian and author Kenneth M. Stamp writes, with regularity. The best or most contented of slaves on the plantation of the American South, from the perspective of the master and/or overseerer, resisted or eluded work in an assortment of ways in an "under-the-radar" manner. Stamp writes, in his book The Peculiar Institution: Slavery in the Ante-Bellum South, from chapter three titled "A Troublesome Property" (pg.108-109), that most slaves:
...were not reckless rebels who risked their lives for freedom; if the thought of rebellion crossed their minds, the odds against success seemed too overwhelming to attempt it. But the inevitability of their bondage made it none the more attractive. And so, when they could, they protested by shirking their duties, injuring the crops, feigning illness and disrupting the routine. These acts were, in part, an unspectacular kind of "day to day resistances to slavery."
True acts of defiance, discounting escape and armed rebellion, were done secretly, under ones breath and with a sense of intent to hurt the functioning of the plantation, the master and/or the overseerer without getting punished themselves. As stated earlier, these subtle acts occurred frequently and were done with "malice" by slaves.