A steam tower consists of a collection of vertical pipes linked by televator gates. One end of each pipe is thus connected to the other end of the next pipe, so as to form a continuous chain through which gas can flow. A typical steam tower is a few stories tall, with a total internal length of over a mile.
The principle of a steam tower is that as steam rises it loses pressure, causing it to expand, which causes it to lose pressure. As the steam expands, thermal energy is converted into mechanical work. Once the steam has passed through the system, it runs through a heat exchanger that condenses it back into liquid water.
Energy is extracted from the steam tower by arranging the televator gates in linked pairs. As steam is teleported down through one pair of gates, liquid water is pumped up through a second pair. Thus, the work done by steam rising over an effective distance of over a mile is used to pump water between two reservoirs at different elevations. The water is then used to drive a waterwheel.
Steam towers are not particularly efficient, but this is not really an issue if the engine is run off summoned heat, such as magma.
As steam runs through the pipes in a steam tower, it causes each pipe to vibrate. Different pipes have different resonant frequencies, resulting in a combined sound not unlike a badly tuned pipe organ.