http://www.edinburgh-scotland.net/images/ForthBridge03L.jpgResearch

http://www.roadtraffic-technology.com/projects/hangzhou/images/7-cable-stayed-bridge.jpghttp://upload.wikimedia.org/wikipedia/commons/6/6d/Hell_Gate_Bridge_by_Dave_Frieder.jpg

 

 

 

 

 

 

http://users.telenet.be/b0y/content/fotos_gen/poulies(2).JPGhttp://www.monarchbearing.com/images/spur-gears.jpgGears

http://www.dreamstime.com/tracks-of-gears-thumb3285106.jpg