File:Chicago view of South Branch Chicago River, Sears Tower observation deck.jpg

photo: 10/11/2004

LATENT CASE: A SLIGHT VERTIGO

The Sears Tower's Skydeck is on the United States's tallest building's 103rd floor: 1,353 ft. above the ground.

People walking on the sidewalks below are as small as mites and other nearly microscopic insects. Cars and vehicles are far less than the size of toys, minaturized to an incredibly tinyness, something that could be held between your finger and your thumb rather than in your hand.

The South Branch of the Chicago River flows far below your feet.

The flow of the Chicago River was reversed by human engineering by the Army Corps of Engineers in 1892 so that it would drain from Lake Michigan rather than into the Lake, thus protecting the purity of the city's water supply fromthe city's own water pollution. It now drains into the Mississippi River basin through the Chicago Sanitary and Ship Canal constructed in 1900 replacing the earlier Illinois & Michigan Canal finished in 1848.

The average sway of the steel frame skyscraper is less than 6" from true center.

My friend, Fay Marie, says she believes she felt that thing swaying when she was on the Skydeck of the Sears Tower. Of course, the Skydeck's staff said the building's sway could not be felt. (Do they know the full range of human ability to detect such sway? It could vary from individual to individual.)

This view out the Skydeck from the "backside" of the building was somewhat alarming and, yet, at the same time, thrilling. Perhaps it was the river running beneath my feet.

The Skydeck is a large space but it is also incredibly open. There aren't any posts or beams blocking your view of it (although the center of the room is occupied by the restroom, etc. It's easy to figure out the dimensions of what is essentially a single large room set high atop a the relatively slender profile of the Sears Tower.

It's the proportion of the Skydeck's width and length in comparison to the vast height of the Sears Tower that preyed upon my mind, perhaps more than anything else.

The Skydeck's total amount of floor space is incredibly small in comparison to the block after city block of Chicago at ground level below. When I think of it this way, It's almost seems that the Skydeck is suspended in mid-air high abover the city.

The Sears Tower is so tall you look down on all the other city's buildings, including all of the other of the city's downtown skyscrapers. The view on a clear day without haze extends 40 to 50 miles from Illinois to three other states: Wisconsin, Indiana, and Michigan.

Sometime after being on the Sears Tower Skydeck Ipictured being in the position you see in the photograph: my feet next to the register at the bottom window which starts very close to the floor. The building starts to sway, losing its balance: the top heavy structure bending over, breaking in the middle, the top half breaking and dropping head first into the South Branch of the Chicago River below.

Sears Tower Skydeck: official website www.theskydeck.com

Chicago Traveler: Sears Tower Skydeck www.chicagotraveler.com/attractions/sears-tower-skydeck.html

Wikipedia: Illinois & Michigan Canal