I gave a talk at the Origins War College in 2003 (?) about the development of the tank (it had been posted in its entirety on the late MagWeb.com site, which is not longer a military history site). Here's a bit of the research text.
Leonardo Da Vinci weighed in circa 1500 with a covered wagon boasting turtle-like armor, slits for handguns, and an 8-man handcranked 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 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.
By 1882, a man named Fender from Buenos Aires designed a chain track driven by a polygonal sprocket with square idler and circular rollers--by all accounts the equivalent of a modern track. The next year, Gottlieb Diamler stuck a gas engine on a bicycle. Although far behind steam power at the time, the development of the gas-powered engine would alter the size and shape of tanks. In 1885, Karl Benz produced vehicles based on an internal combustion engine, followed in 1886 with Gottlieb's car--a gas engine on four wheel carriage.
By 1888, F. W. Batter had a steam-driven tracked vehicle on the drawing boards, followed in 1890 by G. Edwards half-track design: front wheels for steering and steam powered tracks for propulsion.
In 1899, Englishman Bramah Diplock crafted a footed wheel tractor, with improved suspension and cross-country ability, followed quickly by an American, Holt, who built a caterpillar tracked steam tractor in 1906--the first in a long line of such tractors that would inspire designers within a decade.
In 1899, Frederick Simms patented the armored car, and dutifully demonstrated his "motor war car" in 1902. Built by Vickers Sons, this four-wheeled vehicle offered a 16 horsepower Diamler gas engine, armored plating, a revolving turret with two Maxim machine guns, and a system of mirrors that allowed the driver to steer without being exposed.
In 1907, David Roberts produced a gas-powered tractor with caterpillar tracks, followed the following year by Holt. Roberts sold his patents to Holt in 1912. British Major Donoghue suggested mounting a gun and armor on a Holt tractor in 1908, but was ignored. By 1910, the Diplock footed wheel and chain drive was combined and showed promise.
In 1911, T. G. Tulloch proposed a tractor and trailer design that would be an armored carrier of six 12 lb guns, 12 machine guns, and 100 troops. The proposal went nowhere.
In 1912, Australian inventor L. E. de Mole sent a design to the British War Office for a tank remarkably similar to, and in some ways more advanced than, the tank that would be produced during WWI. Although ignored, De Mole's invention offered all-around armored protection, proposed high ground clearance, used tracks (not footed wheels), and steered via "bowing" (flexing the treads). Although Tritton, Wilson, and Swinton get better press, de Mole deserves more credit.
Indeed, the Royal Commission on Awards to Inventors noted in 1919 that de Mole is "entitled to the greatest credit for having made and reduced to practical shape as far back as the year 1912, a very brilliant invention which anticipated and in some respects surpassed that actually put into use in 1916."
been building and painting his own army for Flames of War for a while now.
