Excerpt from a MagWeb article I did based on research for an Origins War College lecture in the early '00s:
Early Designs
The idea of an invulnerable contraption to bring firepower to bear on the enemy has been three millennia in the making. Although every evolution of technology goes through a fanciful stage, the end result--albeit centuries later--made the goal a reality.
In 1332, Guido da Vigevano came up with a windmill-driven, or perhaps we would say propeller-driven, protected cart that was as fanciful as impractical. In 1472, Robert Valturio invented a covered horse-drawn war chariot holding arqubusiers and mounting scythes on the wheels.
He may have been inspired by Jan Zizka of Trocnov, a former guerrilla and later royal bodyguard to King Wenceslas IV. Zizka took over leadership of the fundamentalist faction of Christianity led by John Huss, a preacher in Prague's Bethelem Chapel. In 1412, Huss was excommunicated and fled the city, only to continue preaching throughout Bohemia. Taken into captivity in 1415, Huss was burned at the stake for heresy during the Papal Schism.
The death of Wenceslas created a power vacuum. With Hussites being hunted down and executed, Zizka fashioned a campaign from 1419-1424 around a wagon train of carts. These were not covered, although they did have tall wooden sides with gun ports. The drivers practiced a "circle the wagons" maneuver to create an interlocking wagon fort. Each horse- or oxen-pulled wagon was crewed with about 20 men, half as arqubusiers and crossbowmen and the other half as pikemen. For a time, this moving fortress was unbeatable.
Leonardo Da Vinci weighed in circa 1500 with a covered wagon boasting turtle-like armor, slits for handguns, and an 8-man hand-cranked transmission. He called them "secure and covered chariots which are invulnerable, and when they advance with their guns into the midst of the enemy, even the largest enemy masses are bound to retreat; and behind them the infantry can follow in safety and without opposition."
By 1599, Simon Steven produced two "landships" -- small naval warships put on wheels and powered by the wind.
Despite efforts at production, these early designs would only become practical with enhanced power and cross-country mobility. Technology took some time to catch up, but promising discoveries heralded an accelerated development.
In the 1700s, James Watt did pioneering work on steam engines. By 1770, Richard Edgeworth developed a "portable roadway" for carriages, followed in 1801 by Thomas German's endless chain tracks and footed wheels. Footed wheels used individual pivoting feet (much like a single section of today's tank track) attached on the outside of the wheel. In 1825, George Stephenson worked on steam locomotives for railroads.
Arguably, the first armored engine-propelled vehicle used in war, if it could be loosely considered such, made its debut during the Crimean War in 1854. It was more armored truck than tank, but the machine worked. Created by James Boydell, this steam-powered wheeled tractor was fitted with "footed wheels" and armor plates. It was used to haul supplies, not troops, but the mating of steam power to armor plate to something other than round wheels was a giant step in the evolution of the tank.
In 1855, James Cowen patented a four-wheel, steam-powered "locomotive land battery fitted with scythes to mow down infantry." Andrew Dunlop in 1861 built a footed wheel vehicle, but despite the American Civil War, nothing more occurred with the design. In 1870 during the Franco-Prussian War, an engineer named Balbi designed a similar machine which he called a "mobile fortress," but the French staff rejected the idea. Balbi built two at his own expense, but the Army would not fund further development.
