We have all seen it; those puffs of black smoke that hover over Mount Washington, visible from peaks many miles distant. Those black clouds were spewed from the wood- and coal-powered cog railway locomotives that churn up Mount Washington, ferrying summer tourists to the mountain summit that is reputed to have some of the worst weather in the world, and some of the best views. Coal replaced wood as the primary fuel in 1910, and each 3-mile trip to the summit required more than 1 ton of coal and 1,000 gallons of water! Despite its 139-year history, ‘The Cog’ is attempting to keep up with the times related to global climate change. One of the cog’s locomotives was recently converted to run on biodiesel, so that black cloud may be getting smaller, and the air a bit cleaner. With the new fuel also came a new name: Wajo Nanatasis (pronounced “Wadzo Nanna-tassis”) which is Abenaki for “Mountain Hummingbird.”