So the metal that was probably most important to the British navy during the period that I study was copper, mostly because of these nasty looking little buggers. The naval shipworm, Teredo navalis, consumes wood and has spread all over the world, causing major damage to underwater wood piers, pilings, structures and, most importantly in what I study, to the wooden hulls of ships.

A variety of methods were used to combat the shipworm (and, when navies started moving into the warm waters of the Caribbean and the Indian Ocean, seaweed). One of the earliest that was tried, in the English navy at least, was lead sheathing used over the submerged part of a ship's hull. (This wasn't new to the English -- the Kyrenia ship included lead sheathing, though it seems to have been used to plug leaks -- but newly rediscovered in the 17th century.)

The issue with using lead sheathing on a hull, though, is that English ships of the time were also built with iron fittings that were either permanently submerged (such as the fittings of a rudder), or could be submerged (such as the chains connected to the deadeyes of the shrouds). The presence of lead and iron in proximity in saltwater creates a situation where galvanic corrosion can occur, so though the lead deterred the shipworms, it also corroded the iron fittings of the ship. From an account by Greenvill Collins of a voyage in the 1670s:

the ruther (rudder) being loose they unhung it and hoisted it on deck where they found the pinckle (pintle) irons quite consumed and eaten by the salt of the lead or some other matter which corrodes from the lead that eats the iron and nails.

The English, later British navy, kept experimenting throughout this period with metals to sheath their ships in, and copper seemed to be promising for reasons of lightness, compared with lead (though it was expensive, the savings in ship maintenance defrayed some of the initial cost). Copper didn't fix the corrosion problem, but shipyard workers eventually found out that using lacquered paper between the wooden hull and copper sheathing, as well as preventing the copper and iron fittings coming into contact, reduced the corrosion to a level that was manageable. By the 1780s, the first coppered ships were joining the fleet. The Controller of the Navy, Charles Middleton, reckoned that coppered ships were a knot or two faster than non-coppered, and that coppering increased the available fleet by a third by reducing dockyard maintenance.

For over a decade, a single model of automobile completely dominated the American market - the Ford T. At its peak in 1923, the T represented 55% of automobile production in America. Instrumental to its success was stellar performance in metrics overlooked my other manufacturers: never even close to the most powerful car on the market, nor the lightest - but in power-to-weight it was nearly unparalleled when it was first introduced. With 20hp carrying 1,200 lbs, the touring car ($850 in 1908) boasted a 60:1 weight-to-power ratio: while a top-of-the-line luxury tourer such as the Oldsmobile S or Pierce-Arrow Great Arrow would easily outrun a Ford (with 28 and 32 hp, respectively), their considerable weight (2,300 and 2,700 lbs) pushed their weight:power ratio to 82:1 and 84:1. Even the Buick model 10, with its spunky 22hp overhead-valve engine and price point just $50 more than the Ford, only managed a 80:1 ratio. Only the magnificent Thomas Flyer, winner of the 1908 New York to Paris transcontinental race, achieved a similar ratio at 64:1 - but its $3,500 price tag put it well out of the T's market.

The secret to Ford's outstanding performance lay in its pioneering use of vanadium-steel alloy, which offered higher tensile strength to lower weight than other steels and was easier to machine. It was used extensively throughout the model T - the axles, springs, wheel spindles, and transmission gears, reducing weight while keeping the car strong and flexible (flexibility was itself another major innovation of Ford - where luxury touring cars relied on a stiff chassis and secure four-point motor mounts to maintain rigidity and ensure a smooth ride, Ford used 3-point motor mounts and flexible chassis rails, allowing the car to flex without damaging the engine block). Ford had first introduced vanadium steels in 1907, in the Model N runabout (a precursor to the T, and itself one of the most popular cars in America at the time) and model K luxury touring car, but even by the time model Ts began appearing in significant numbers in 1909 Ford remained the only American manufacturer to use the material extensively.

So where did Ford get this brilliant idea?

Well, if you read Henry's rather self-serving 1922 "autobiography," My Life and Work (actually written by Samuel Crowther) he will tell you on pages 65 and 66 that in 1905 he was attending a car race in Palm Beach, FL where one of his luxury six-cylinder model Ks had been entered. During the race, a French car was involved in a large crash that sent pieces flying over the racecourse. Henry found a valve stem from the French racer, and upon picking it up was immediately surprised by its light weight and strength. He gave it to his assistant and told him, "find out all about this. That is the kind of material we ought to have in our cars." And the rest is history - upon determining that it was vanadium steel, Ford set out to find someone who could make it for him, only to learn that no steel maker in the US had furnaces got enough to make the alloy - so he financed one himself, bringing in an English metallurgist to oversee the process. This story can be found as early as 1907, when it appears in the March 24 edition of the Inter Ocean newspaper.

However, there is reason to believe the story is apocryphal. Extensive descriptions of vanadium steel had been published in European scientific and engineering journals read by Ford executives, and had even been presented at a 1905 engineering convention attended by a chief Ford executive. Historian Douglas Brinkley suggests that C. Harold Wills, Fords most influential designer (he designed the removable engine head and planetary transmission used in Ford cars, and the Ford script logo), was the one who brought the material to Henry Ford's attention; despite their relationship cooling to the point that Wills was denied access to the room where the prototype T was being built, Ford had Wills in charge of developing the steel for the car. What's more, the aforementioned British metallurgist had been previously retained by Wills as a consultant. Perhaps because of their souring relationship (Wills left the company in 1919, eventually starting his own innovative, but short lived, auto company, Wills Sainte Claire), Ford decided to write him out of the story - something he is known to have done with other folks.

However, there is yet a third account, supposedly straight from the lips of Ford himself. In the January 24, 1909 edition of the Los Angeles Herald, an item quoting Ford states that experiments on the material run by the US Navy were the inspiration; after hearing from one Commander Davis that the material withstood considerable strength (the article describes the test being of a vanadium cannon inside a torpedo ... I am having trouble picturing how that works), Ford "immediately took steps to place it in use in the manufacture of his own cars." The timeline here is a little uncertain - the article was published in 1909 but mentions no dates, but Ford had been making vanadium steel on contract with a Ohio steel mill since 1906.

The true origin of the idea is still murky, but as far as things go it is really just a minor piece of trivia.

Sources:

•Drive!: Henry Ford, George Selden, and the Race to Invent the Auto Age by Lawrence Goldstone
•Wheels for the World: Henry Ford, His Company, and a Century of Progress by Douglas Brinkley
•"The Road to the Model T: Culture, Road Conditions, and Innovation at the Dawn of the American Motor Age" by Christopher Wells, published in Technology and Culture, Vol. 48, No. 3