Atop Mount Washington: Da Vinci, Aerial Perspective, and the top of New England
August 17, 2016
Photographer: John Stetson
This picture of my son, Peter, was taken from the summit of Mount Washington, 6,228 ft (1,917 m), during the annual Mt. Washington Bicycle Hillclimb. Note the bluish colors of the mountain ranges in the mid-ground and background. Leonardo Da Vinci wrote the following about aerial perspective: "... the remotest objects ... appear blue and almost the same hue as the atmosphere," and also this "(Anything) you wish to look furthest away, you make proportionately blue."* To see Da Vinci's aerial perspective in practice look no further that the background of the Mona Lisa.
The reason why the more distant ranges have a blue tinge is because of the effects of airlight and haze. In essence, the further away the ridge, the greater the number of air molecules available to scatter sunlight. This is especially true on hot, humid days when water vapor is abundant.
The last 100 yards (91 m) of the Mount Washington race includes a 22 percent grade. Some cyclists are going so slowly at that point that they loose gyroscopic stability and need the assistance of spectators to keep them upright. Wind and weather can also present a challenge to cyclists; one fellow cyclist, while facing a 40 mph (64 km/h) headwind on the ascent said that this was one experience that he could recount without having to exaggerate. In 1934 the observatory recorded a wind speed of 231 mph (372 km/h), a record for recorded wind speed at that time. Photo taken on August 24, 2002.
* from the Notebooks of Leonardo Da Vinci, Chapter 5.