SLO-TRANS

'Slo-Trans' is a fictional engine in Stephen King's ''The Dark Tower'' series.

Contents

The Engine

Charging the Batteries/Capacitors

The Engine

The engine is frequently mentioned as being heard, such as in some castles, and is mentioned at one of the base stations of the Beam of the Bear (Shardik).
The last surviving Slo-Trans engine was found in Blaine the Mono (see ''The Waste Lands'' and ''Wizard and Glass'').
(Note: an unnamed mono is mentioned in ''Black House'' as well, after Jack rescues the kid.)
The Slo-Trans engine was designed by North Central Positronics; the only two ever known to exist (by the Ka-tet) were in twin trains stationed in the city of Lud.
These very powerful engines were used to rapidly transport passengers over long distances, and were powered by an advanced battery or capacitor that lasted between 4 and 6 hours at full output.

Charging the Batteries/Capacitors

If the destination was too far away that a single charge would not last the whole trip, the engine could make a pit stop and recharge. During the eight hour trip between Lud and Topeka, Blaine had to make one such stop.
The engines were initially charged in its home station before leaving. The only pit stop mentioned in ''The Waste Lands'' and shown in ''Wizard and Glass'' was located at a waterfall, The Falls of the Hounds, which provided the train with power. However, it is expected that there were many other places like this, with varying sources that supplied power. It is hinted that Slo-Trans engines can draw power directly from the Beams; this could imply that Slo-Trans technology is partially magical in nature, or that the engine is merely designed to work on the same power source that the Great Old Ones used to power the Beams when they replaced magic with technology.