Why Narrow Gauge? II

Whiplash Curves

Away back in the 1970's someone made a film that started with episode 4.  After many years they filled in the blanks and are now up to an episode somewhere north of 7.  The following is listed as II but there are at least 2 posts in the works that come before this and the same number last year that gave a side handed approach to the subject which you can find if you dig through the index.  I don't know how many follow, it just depends on how carried away I become in the writing.  Be patient I will get to ones prior to this one before G and I return to Chama next August.

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The journey from Antonito to the summit at Cumbres and beyond to Chama is a study in Geography, the "lay of the land" so to speak.  This Geography, or terrain, establishes the route while Geology, the composition of the land, establishes the building techniques which range from simple grading on level ground to complex trestles, cuts, fills, and in the extreme tunneling.

Most railroad fans, it seems, like the telling of the story eastbound from Chama.  I really enjoy the telling this story from a westbound perspective starting in Antonito.  This is the direction in which the railroad was built and to me it makes it is appropriate in the telling of the story.  So, let's take a trip on a 64 mile railroad built in the mountains of Colorado and New Mexico in 1880 over 270 days and talk a bit about railroad civil engineering and construction.

The challenge from both directions is the climb to Cumbres which is in excess of 2,100' from both ends.  Westbound out of Antonito the grade never exceeds 1.42%, or just under an average of 75' per mile, (ruling grade) and the climb takes 51 miles.  The ruling grade of 1.42% is not consistent.  There are places such as the run from Tunnel 3 to Osier, MP 314.3 to 318.03, which is essentially level as is the run from Antonito to Fergueston Trestle MP 280.0 to MP 285.6.  If the grade was consistent the total climb would be over 3,800' so how do we account for the missing 1,700'?  Let's get on the train and go to the open car to hear the locomotive, get covered in ash, see the spectacular scenery and hear the story of building the railroad told yet again.

Leaving Antonito for Chama the train has a run of just over 5 miles on a slight grade to a point just beyond Fergueson Trestle (Upper red mark on picture).  A "ridge" running to the southwest is prominent to the west as we leave the Depot.  At Ferguseon trestle the track turns southward to parallel the ridge and commences a climb up Gravity Hill.

Plateau west of Antonito

The First Step - Gravity Hill

The ridge is actually a narrow plateau with a cap of volcanic breccia - Whiplash Curves are marked with the red circle.  The toe of this plateau is 400' above the plane on which the railroad runs at Ferguseon Trestle.  It is eight miles long and runs to the southwest.  Appearing dead level it actually inclines upward 500' from the toe near Ferguseon Trestle to the southwest at which point it is 900' above the cold desert at Ferguseon Trestle.

The climb up Gravity hill is a consistent 1.42% until reaching Lava Tank (Picture 1 - Lower Red Mark).  This run is the first of three long steps each of which runs from relatively level land to an abrupt climb.  The first step, up Gravity Hill brings us to a broad mesa which falls off to the Rio De Los Pinos 400' below on the south.  At the lower end of the Lava Tank Loop the rails have climbed to 8,479' over 500'  above Antonito the majority of which, over 350', was the 5 mile journey from Fergueson Trestle to Lava Tank.

The Second Step - Whiplash Curves

The second step commences as the train enters a life zone change and we see pine trees and Aspen.  as the train winds through uneven terrain; we cross numerous small fills which were first constructed as trestles to save money and expedite the construction.

We are in just inside Colorado here and slowly we approach an escarpment on which the railroad grade traces a pattern across the face, this is the "Whiplash Curves" (Picture 2).  At this point, the site of the long gone Big Horn Section House, the train begins a one and one-half mile climb from the base of the southern escarpment to the top of the plateau we originally viewed in Antonito.

Though the grade varies little from the previous 6 miles, we now traverse two complete reverse curves which tightly compresses the 110' climb into a limited amount of space.  Space is so limited the near 500' sweep of the 20 degree reverse curve on the top just brushes the edge of the northern escarpment. With this we surmount the plateau first seen to the west of Antonito; this second step took 7.5 miles from the lower loop of Lava Tank and a 400' climb.  The northern sweep of the curve is 8,872' over 1,000' above and 17 miles beyond Antonito with 34 miles and a 1,100' climb remaining to Cumbres and the "dreadful drop."

As we gaze at the Whiplash Curves from above our train journeys on, entering a land of complex geology and wondrous views.  We will soon see why this has been called "...The best example of narrow gauge steam operation in America...", in the National Historic Landmark award, and why the entire rail bed was awarded Landmark status by the American Society of Civil Engineers.  We will also see why, in 1885, Toltec Canyon was described as, "The King of Canyons".

The third step is very different but, that is another story...

The Third Step

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As I tell this ongoing story I admit that I am not a railroad civil engineer.  My grandfather and father were ran a structural steel fabricating and erection business in the Midwest and taking after my forefather's my son is a civil/environmental engineer.  I am retired from another profession but love history, railroads and things historic.  I have restored a home under DOI historic preservation guidelines and thus understand "the drill" when it comes to historic preservation.  This multi-part story is told based on my love of family, railroading and things historic.  It is told in language non-professionals hopefully understand, so if you an engineer or other professional of sorts, please excuse any goof-ups in my telling of this wonderful story.