Vertical splitting relies on showing⁄hiding the top and bottom borders of adjacent cells. For further information on borders see Table and cell borders.

Let's start with a 4-cell table:

Cell 1 | Cell 2 |

Cell 3 | Cell 4 |

Figure 1

Think of each cell as having four borders, like this:

Cell 1 | Cell 2 |

Cell 3 | Cell 4 |

Figure 2

To avoid grid thickening, either the upper cell's floor or the lower cell's ceiling may be visible, but not both. (Occasionally you may notice a double thickness grid wall but this will disappear when you return to the article after moving to another node or closing the file, so is an artefact.)

Cell 1 floor visible | Cell 2 |

Cell 3 ceiling hidden | Cell 4 |

Figure 3

Cell 1 floor hidden | Cell 2 |

Cell 3 ceiling visible | Cell 4 |

Figure 4

Cell 1 floor hidden | Cell 2 |

Cell 3 ceiling hidden | Cell 4 |

Figure 5

Note the misalignment in the floors of Cells 1 and 2 in Figure 3 compared with Figure 4, due to different show⁄hide selections. If you notice this when creating your own tables, ensure that these parameters match across the whole row.

We have thus "combined" cells 1 and 3, so let's add some blank lines and rename the combination Cell 5:

Cell 5 |
Cell 2 |

Cell 4 |

Vertical splitting is essentially the reverse of this.