View from rear of timepiece.  The Great Wheel at the bottom shows the brass pins in the spokes with the clickers mounted in the front.  Also the ratchet is visible with the left clicker engage onto the ratchet.  The Great Wheel engages the second wheel's pinion right above and to the right.  The second wheel engages the third wheel's pinion to it's left.  And
finally the third wheel engages the escape wheel's pinion above and to the right.