Why was the protractor invented

By the seventeenth century, protractors were standard tools for navigation at sea by sailors. It is also used for navigation at land. Joseph Huddart designed more sophisticated versions of protractor in for calculating ship position at sea. This protractor was named three arm protractor because it had a circular scale and three arms.

Two arms are rotatable, and one central arm is fixed so protractor can set any angle relative to the center arm. By the eighteen century protractors were widely used in geometry and mathematics, by the nineteenth century, a lot of different versions of protractors appeared and by the twentieth century the protractors became standard for school mathematics.

Protractors can be made in various shapes: most popular semi-circle, full circle, square, rectangle, sixth circles or quarter circles. When civilization was in its infancy, people needed a way to understand and calculate a variety of tasks, including bartering food and raw materials, making clothing, and constructing buildings that would collectively form cities, communities, places of worship, and more. This is where the importance of measurement systems becomes glaringly obvious.

There are entire books worth of information about the history and impact of ancient measurement systems. We owe a lot to the Ancient Greeks when it comes to the design of our modern day measuring devices—the Greeks invented many of the tools that we use every day. But how did we get by before we had this technology available, and what are some tools that we still use to this day?

One of the most important aspects of building design and maintaining strength in structures is keeping a level construction.

One of the earliest designs of the level was used by the Romans and had a letter A-shaped frame with an additional horizontal bar on top. This tool was critical in building entire civilizations, and beyond determining plumb and level, the libella also acted as a square and even a ruler if needed.

The Egyptians built the pyramids and the Greeks built ancient temples—all with the help of the level.

The protractor, used for measuring angles, has a possible history that dates back to around BCE. In the tomb of an ancient Egyptian architect, Kha , researchers discovered a unique shaped object that has been debated over for many years. Protractors have been used for thousands of years for measuring and drawing angles along and also served a very important role in map preparations and navigational charts.

I find it very useful to know that it was used first in navigation, designing maps and astronomy than in a geometry textbook. Hope you liked this short post. Let me know if you would like to see similar ones. Feel free to comment bellow. Have a great day. We will try to post there as often as possible. Like Liked by 1 person. Very nice short summary of the history behind the protractor. Btw, it would be very interesting to know how did they measured angles before.

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