Synecdoche

synecdoche: a figure of speech in which a part of something stands for the whole thing. In the expression, "I've got wheels," wheels stands for the whole vehicle, usually a car. Be sure you can distinguish this from metonymy

"The slave auctioneer's bell and the church-going bell chime in with each other,"
                                                                         -Narrative of the Life of Frederick Douglass
                                                                                             by Frederick Douglass

The "slave auctioneer's bell" here stands for the institution of slavery and its horrible practice of tearing families apart. While the "church-going bell" here refers to the claimed Christianity of the south. Using these two "parts" instead of the overarching systems spares the reader from irritating and tiresome repetition, and highlights different aspects of the respective institutions. When a slave auctioneer's bell rang it meant the tearing apart of a family, or friends at the least. However, the church bell was rung to call people together. This is another example of the hypocrisy of the "slave-holding religion of the land," which Douglass works hard at invalidating.