Witten / Ruhrgebiet, Zeche Nachtigall: steam engine main rod
Due to the imaging characteristics of my uncoated Summar lens this photo gives the impression of motion (in fact there was nothing moving here).
This is the main rod of one of the oldest steam engines which has been preserved in the west german Ruhr region. The engine served the mining industry for several decades; it follows the "compound" principle (meaning that the steam first "works" in a smaller cylinder where it looses part of its pressure and then streams into a much larger low pressure cylinder to "work" once again which helped to reduce fuel consumption).
I took this image more or less on the very spot where German coal mining started in the 18th century. The beginnings were humble and primitive; later they dug a deep mining shaft (450m!) to exploit the deeper areas of the coalfield. The steam engine which is depicted above moved the conveyor cage of the mine. The whole area is a museum now. Information about the site is to be found here: www.lwl.org/LWL/Kultur/wim/S/witten/
The steam engine is regularly working (but due to the lack of a steam boiler they don't operate it with steam any more but with compressed air). It's amazing how precisely everything runs - you hardly feel any vibration!