Trundle wheel
The trundle wheel is a measuring device, a simplified form of a surveyor's wheel. It is commonly used by people who need an easy way to find the rough distance from one place to another. The trundle wheel is composed of a wheel, a handle which is attached to the axle allowing the trundle wheel to be held easily, and a clicking device which is triggered once per revolution of the wheel. Trundle wheels are not as accurate as other methods of measuring distance but are a good way to get a rough estimation of a fairly long distance over a good surface. The Trundle wheel was invented by Hugh Boylan in the late 1970s when he worked as a Quantity Surveyor for a small Irish Engineering company. There were patent issues with the device and after court proceedings the company won the rights to the patent.