The space shuttle was originally designed to propel itself, both on returning from a mission and in hopping among various landing sites. When air-breathing engines were judged too heavy and costly, NASA had to find another way to move the shuttle around.

One unlikely candidate was the Virtus, a pair of B-52 fuselages mounted to a giant wing. Proposed by American aviator John M. Conroy, the aircraft would have had a wingspan of 140 meters and a takeoff weight of 850,000 pounds.

Prototypes performed well in the wind tunnel, but the prospect of building, testing, and accommodating a new aircraft, and especially such a large one, finally argued against it, and NASA decided to piggyback the shuttle on a 747.

In the 1920s, Fiat’s car factory in Turin, Italy, contained a spiral roadway — raw materials went in at ground level, and the cars ascended as they were assembled. At the top they emerged onto a test track on the roof.

Lauded at the time, the factory was eventually outmoded and has since been remodeled into a hotel and shopping mall, but the test track remains and is open to visitors.

During daylight hours on the Western Front, soldiers in World War I regularly inspected the no-man’s-land that lay between the trenches. To do this they used either telescopes slid between the sandbag defenses or periscopes, which could be raised above the parapet to give a view of the field via a pair of reflecting mirrors. Normally there was nothing to see, but Brigadier Philip Mortimer of the 3rd Meerut Divisional Train had a start one day while peering through a telescope:

I actually saw as clear as daylight, the reflection in the top mirror of his periscope, a German officer’s head as he searched our trenches through his periscope, a most uncanny sight — the grey peaked cap and face as he looked down into the bottom mirror could be clearly seen.

“It was decided to ‘strafe’ the periscope with a Maxim which after being trained on it carefully was let off to the tune of about 15 rounds. The periscope immediately disappeared.”

(From Richard van Emden, Meeting the Enemy, 2013.)

When inventor Guy Otis Brewster offered his Brewster Body Shield to the soldiers of World War I, he demonstrated its efficacy by standing before a Lewis machine gun firing bullets at full velocity, about 2,700 feet per second.

All that energy heated the breastplate, but Brewster said he felt “only about one tenth the shock which he experienced when struck by a sledge-hammer.”

Unfortunately the armor weighed 40 pounds, which made it cumbersome in the field.

(Bashford Dean, Helmets and Body Armor in Modern Warfare, 1920.)

At the turn of the 20th century, rural cooperative associations found a way to install telephone networks without erecting poles: They simply connected their wires to the existing pasture fences.

“Fifteen or twenty farmers in Clay Township, Cass County, are enjoying the privileges of first-class telephone service without the annoyance of a monthly collector thrusting a bill for rental under their noses,” reported the Washington Post in 1903. “Their homes are connected by a system of wires, and the novelty of the plan lies in the fact that the barbed wire fences are utilized as a conveyor of neighborhood gossip. Just who conceived the idea that these strands of wire that for years had served only one purpose could be made to do a double duty is not known.”

Maude Smith Galloway and her husband arrived in Texas in 1906. “We talked to a few close neighbors over a telephone hooked to a barbed wire fence when we came to Llano,” she said, “and now we have the dial system and can talk to any of the rural districts in the country.”

Historian David B. Sicilia wrote, “Barbed wire unwittingly became part of the nation’s budding telephone network. What kept crops and animals apart helped bring people together.”

(Alan Krell, The Devil’s Rope, 2002.)

Marco Polo noticed an interesting feature in the architecture of Hormuz: “The heat is tremendous, and on that account their houses are built with ventilators to catch the wind. These ventilators are placed on the side from which the wind comes, and they bring the wind down into the house to cool it. But for this the heat would be utterly unbearable.” This technique has been used for thousands of years, originally in ancient Iran and now throughout West Asia: By catching the prevailing wind and directing it through the interior of a house, the residents can greatly increase air circulation while avoiding the sun’s heat.

In 2005 tests using a wind tunnel, Vipac Engineering confirmed that windtowers are effective in reducing the impact of summer climate — and their passivity makes them valuable for energy conservation.

(Anne Coles and Peter Jackson, Windtower, 2007.)

Inventor J.F. Webb proposed this curious safety device in 1910: If your flying machine fails, you release a domelike “air anchor,” which pulls open three parachutes beneath it. These will “sustain the machine sufficiently to break its fall, thereby permitting the machine to descend at a safe speed.”

In The Big Umbrella, his 1973 history of the parachute, John Lucas writes, “Whether Webb’s device worked or not is unknown, but eighteen years later a single parachute 84 feet in diameter and strong enough to support a loaded plane was developed by the U.S. Air Corps.”