This page originally appeared on Thomas Ehrenreich's Railroad Extra Website
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This page originally appeared on Thomas Ehrenreich's Railroad Extra Website
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HARPER’S WEEKLY
NEW YORK, SATURDAY, OCTOBER 19, 1867
On our first page we need give an illustration of Mr. Needham’s Pneumatic Railway which is on exhibition at the American Institute, and which is attracting great attention from the thousands who visit the Fair. The invention is one of great value and importance, and it is impossible to imagine the extent of the revolution which it may yet produce in passenger transportation in our great cities.
This invention is really only an improvement on the Pneumatic Railway which has been in successful use for some years in London for the conveyance of parcels; and it demonstrates the practicability of conveying passengers in a tube with speed, safety, and comfort. When it is known that two tubes seven feet in diameter, can be laid for about $50,000 per mile, and that once laid the cost of operating it is less than that of a horse railroad, it will attract the attention of capitalists.
The principle of propulsion in Mr. Needham’s invention differs from that of the London or Rammel invention in that while the latter only drives the car by the force of air compressed and blown into the tube, the former also draws it by the power of suction. While one engine fans the air in at one end another sucks it out at the other; and thus the car is at once propelled and drawn with great velocity through the tube. This is the great power, and will act for great distances; and when the resistance is removed from the front the propelling force is proportionally increased in the rear.
This principle was put to use in New York City; it didn't last long. Here are two diagrams of this set-up.
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