Old Peppersass: The little engine that could
Marsh knew that in order to make his railway feasible, he needed to solve many complex problems. Chief among them were his chosen route’s rugged terrain and its steep grade, averaging 25% and nearing 38% in some spots.
He solved the terrain problem by specifying that the three mile route would be built on an elevated trestle system, and that was probably one of the easier decisions he had to make. To this day, the Cog is the only railway in the world whose mainline tracks are built entirely above ground level.
It’s also the second steepest railway in the world, and maintaining traction on such steep grades would be unthinkable on a traditional railroad. It would take an entirely new concept to make it work.
The cog gear and rack were not Marsh’s invention, but the application of that technology to a mountain climbing railway certainly was. The idea is very much like the sprocket and chain on a bicycle. The teeth of the cog gears under the locomotive engage the rack, a spooled center track fixed to the cross ties between the running rails, and as the cog turns, the locomotive pulls itself forward. See the animation below.
Shortly after receiving his charter from the State legislature, Marsh was distracted by a lawsuit over property he owned back in Chicago. The dispute was successfully defended in 1860 by his able attorney, and happened to be Abraham Lincoln’s last court appearance prior to his election as the nation’s sixteenth president.
Construction progress was delayed by the American Civil War, so it wasn’t until 1866 that Marsh took delivery of the railway’s first locomotive. Built in Boston at a cost of $2000 and originally named “Hero”, the odd looking machine quickly earned the nickname “Old Peppersass” because of its trunnion mounted, self-leveling vertical boiler’s similarity to a pepper sauce bottle. Marsh devised an ingenious system of using air pressure in its steam cylinders to safely control the engine’s descent.
The first 600 feet of track was completed quickly, including a trestle bridge spanning the Ammonoosuc River. A demonstration for government officials and investors was presented in late August (seen above). Peppersass performed admirably, and for Marsh and his dream, the sky was now literally the limit.
Celebration marking the 60th anniversary of the railway , July 20, 1929, and Peppersass’ final climb on Mount Washington.