Accidentally crossed jumper cables on Volvo 1995 850 starter turns over but engine will not fire did I blow the coil or a fuse?

Accidentally crossing jumper cables can cause electrical damage, but it may not necessarily blow the coil or a fuse. First, check the fuses related to the ignition system; a blown fuse could prevent the engine from firing. If the fuses are intact, the issue might be with the ignition coil or other components in the ignition system. It's advisable to have the electrical system and components tested to identify any damage.