vacuum wins

A reincarnation of Otto von Guericke's hemisphere experiment invented in anno 1650. 12 horses, 6 at each opposed sides, try to divide two hemispheres that are connected air proof with all air being pumped out from the cavity (see the silver-coloured sphere). All those horses pulling with their mass and impetus do not succeed, although these are strong "cold blodded" working horses... vacuum wins and grins about the effort.

Never mind: nothingness is your friend. See here.