JF Ptak Science Books Post 2755
I don't mean to appropriate the past from my seat here in the future, raising my eyebrows over what definitely seems to be an Ig Nobel engineering effort, but, well, there are times when you distill a bad idea over a low flame that the bad idea distilled is still a bad idea.
I've tried to imagine the circumstance in which this bridge would make sense, particularly in light of the fact that it was a proposal by J.W. Morse to counter the Roebling plan to erect the East River (later “Brooklyn”) Bridge in about the same location. This is how this bridge plays itself out in my mind: a suspension bridge of some substantial size is constructed to carry a ferry from Manhattan to Brooklyn, even though it seems that a ferry would be able to get from one place to the other with not terrible fuss, except in the old style of using a boat it would be moving on/in the river rather than over it. The ferry wouldn't need a bridge to cross the river if it didn't wholly depend on one from completing its task, which ferries almost never do, being watercraft and all.
The details of the plan are a little shocking: that “car” hanging from the bridge cables measured 160'x40' (6400 square feet) and two storeys high, and was meant to carry 5,000 people at one time (75,000 over a 12-hour period) along with another 500 horses and carts on the lower level. It was to make the trip in a minute or two, and would be moved from one point to the other at a few feet above the river.
This might make sense if the river was choppy, or ice-bound, at which point it would be nice to use HyrdoplanePunk to get across the river. A bridge-as-bridge would accomplish this task without turning itself basically upside down and inside-out.
As I said it is not so good to judge application of technology by a modern standard; though in this case it seems as though if you were to look just slightly into the future from 1869 that you'd realize a continuous flow across the river would be highly preferable to a car shuttling a limited number back and forth. In addition to numerous other issues, I'm not sure how the engineer was dealing with the traffic and congestion caused by the fits and starts of 1,000 or 2,500 (let alone 5,000) people plus freight leaving the car/boat all at once, joining a crowd of people and horses and so on waiting to board, dozens of times a day.
At the end of it all, this bridge is also just not very attractive, and not made for the ages—it seems temporary, a short range solution to a long range issue, something soon to be dismantled, used elsewhere, and then scrapped.
I should point out that there is a variety of bridge dedicated to this sort of transportation—it is evidently of French origin, and referred to as a pont a transbordeur, and seems to have some utility here and there, though that “here” and “there” did not include “Manhattan” and “Brooklyn”.
- From the article: "While plans have now been divulged to connect the island of Manhattan in New York with Brooklyn by means of a giant suspension bridge over the East River, Mr. J. W. Morse has devised a bridge which permits of a much lighter construction than a normal suspension bridge and is, consequently, much cheaper to build. Mr Morse's project provides for transportation across the river in a giant platform, suspended by means of cables from a trolley running upon a gantry across the river. Measuring 40 X 160 feet, the platform has two stories: the top floor is for pedestrians while the bottom deck is intended for horses and carriages. While a normal suspension bridge requires extensive abutments and ramps to enable the road traffic to reach the bridge-deck level of almost 120 feet, Mr. Morse's transporter bridge obviates the need for such provisions. The fact that the traveller [sic] hangs only 3 feet above the water-and hence is almost at street-level-makes it easy for heavily loaded wagons to cross the river, and will also be appreciated by the workman returning home on foot after a hard day's toil in the factory or warehouse." --Scientific American, 24 May, 1869