No. 3 - the Citroen 7CV
The Citroen 7CV Traction Avant ('Traction Avant ' is French for 'front wheel drive') was, in many ways a revolutionary car. It was not by any means the first FWD car on the market; it had already been beaten to that by Alvis in the UK, which used this technology in a racing car, and Cord in the United States. However it was the first car to be driven through the front wheels of a vehicle with a monocoque steel body, with independent suspension on all four wheels. The absence of the usual steel chassis under the car meant that it could sit far lower than the majority of vehicles on the market, giving it a very noticeable appearance.
The monocoque system, which virtually every car in the world uses nowadays, gave a great saving in weight compared to the traditional heavy chassis, resulting in better performance and economy. Initially many people were sceptical that this would be strong enough to put up with the rigours of day-to-day driving and so in a publicity stunt one of them was deliberately run off a cliff; two gentlemen then replaced the bonnet which had been knocked off and then drove it away! You can see a video of this HERE
To add to the car's desirability it had hydraulic brakes all round, rack and pinion steering and independent torsion bar suspension.
Sometimes however a car can be too successful. Designing the car and creating a production line for such a revolutionary machine is expensive. The race developed to get the car into mass production before investors lost patience, and money ran out. In 1934, the year of its launch, these costs pushed Citroen into bankruptcy.
The company was bought by Michelin; they went on to produce many different variants of the 7CV with constant improvements over the next couple of decades and production only ended completely in 1957, with more than three quarters of a million cars sold in the meantime.