401
BNSF train rounding the Tehachapi Loop in California.
402
The Rolling Bridge at Paddington Basin by Thomas Heatherwick.
403
Joining fiber optics with a Fujikura 90R mass fusion splicer.
404
Loading a cargo riverboat with ferrous metal using an electromagnetic crane.
408
Non-Newtonian liquids turn solid when impacted with sufficient force through "impact-activated solidification", demonstrated at The University of Chicago by Scott Waitukaitis.
409
A squirrel tries to hang onto a Yankee Flipper Squirrel-Proof Bird Feeder.
410
M45 Quadmount turrent fitted with M134D Miniguns by Dillion Precision Products.
411
Rock picker for clearing fields by Flexxifinger.
412
A Congreve clock or oscillating path rolling ball clock uses a rolling ball instead of a pendulum to regulate time.
415
h/p/cosmos saturn 450/300 rs "The Beast" treadmill.
418
Demonstrating how earthquake dampeners work.
419
Friction drilling allows stronger holes to be drilled by pushing material instead of removing it, via AvE.
420
Janney coupler between train cars, via the Fairfax Station Railroad Museum.
421
Real-time projection mapping onto a face, by @nobumichi_asai.
423
Realistic and interactive robot gaze and interaction by Disney Research.
424
Swaging a loop in steel wire rope with a 4,000 ton Z94 Down Stroke Swaging Press by SAHM SPLICE.
425
Kerf bending plywood by Measured Workshop.
Amazing feats of engineering. Tweeted by @kane and root.vc.