The Celestial Etheroscope, a highly complex and expensive piece of machinery, was originally invented on the plane of gears by a long-forgotten sect of lawful soothsayers. Apparently these cutters believed that all things come in cycles and if a blood could measure the point on the cycle where he currently resides, he could work out the future.

It seems this proved too difficult even for the engineering insight of the sect, but they did manage to make some other fascinating devices, not least the etheroscope. Somehow it measures the planar flux and can be use to warn of planeshaking events...

 

Close Encounters
(by Raph)

The Modron Ranks
(by Robert Hays)

Animated GIF of all lower class modrons, plus a decaton, nonaton, octon, septon, hexton, quinton, secundus, and Primus:

Individual PCX files with the 'ready' and 'action' pose for each Modron can be found here:

Mechanical Vista

Being a modron's-eye view of the glory of the gears