View of the top of the starboard diesel engine. Visible are one of the brass cooling water thermometers, the cooling water lines, fuel lines, and the pairs of intake and exhaust valves of the cylinders. Diesel engines do not use spark plugs - it is the heat generated by the compression of the air in each cylinder during the compression stroke that ignites the fuel. These four-stroke engines were made by MAN. The large gauge near the top of the photo is the fuel service counter, measuring the number of liters flowing from the diesel gravity tank in the overhead to the diesel engines. It works just like the water meter in your home. (Caption courtesy of Matt Hamacher)