This is what the hyperbolic tachymeter scale
link (based on the calculation y=3600/x, where x is time and and y is the resulting speed) would look like if you don't worry about the first 15 seconds of the scale and focus on every speed after that point. This was more common on old "snail dial" chronographs back in the days when things (including cars) moved a lot slower. But instead of placing the scale
link in the center of the
link dial, Tudor put it on the rehaut.