James Fergusons Mechanical Paradox Orrery

[Sunset Machine]

Okay- one gear apparently cut normal and the other two have more teeth than normally used on a given OD, making their teeth smaller and moving in smaller increments for each tooth as they engage a common pinion.

But the text describes something else:  one gear moving backwards. So many teeth that its mate misses the peak and instead pushes it away? Do we have tooth counts for doing this? A pointy tooth form is indicated, yes?
Fascinating, thanks Chris.