My apologies.
There are three tests. The first is horizontal gaze nystagmus. Horizontal gaze nystagmus is the involuntary jerking of the eyes. Everyone has it, but some drugs enhance it to the point at which it's readily visible.
The second test is a walk and turn test. That's walking a line heel to toe, nine steps up the line, nine steps back down the line, making a turn in a prescribed fashion while watching your feet, counting out loud and not stopping until the test is completed.
The third test is a one-leg stand, where the person stands on one leg with the other one raised, with the foot elevated approximately six inches off the ground, the toe pointed. The subject looks at their foot and counts out loud, “One-thousand-one, one-thousand-two, one-thousand-three”, until 30 seconds has elapsed.