I could be wrong but them look like heat sinks, you know like on a water cooled CPU in a computer. Water would run into one and out of it and the water would remove the heat from the side of it. Thats just what it looks like to me i could be wrong.

Great set Motts i've always loved your work! you inspired me to gout and buy a Nikon D40 and start heading to my own abandon places.