In 1940 war hysteria gripped New Zealand and an effort was made to produce a home grown tank. It was decided to armor an International Harvester* caterpillar tracked farm tractor to make use of equipment on hand. The result was an amazing "tank" called a "Bob Semple" after a New Zealand politician. Bob was a popular, colorful, Labor politician. The front gunner had to lay on a mattress on top of the engine in order to fire his weapon! The Semple had a top speed of 24 km/h but had to slow down or even stop in order to shift gears. The "tank" was highly unstable and was top heavy. The Public Works Department offered to convert their entire fleet of 81 into Semples at a cost of only 4200 pounds sterling apiece. The army took them, tested them, and even paraded them around the country to improve morale. Only 4 units were built. The Bob Semple was armed with 4 machine guns, it was 12 feet tall had had a crew of 8 men. The reported weight was from 20 to 25 tons.
*Janes reports that the type of tractor was an International Harvester but it may have been a Caterpiller brand Cat DH-8 was used.