Automatic Calculator

During the twentieth century automatic calculators were commonly used by engineers and scientists to assist with calculating both basic and complex equations. Due to the speed and accuracy of this technology (much like the typewriter), it became a desirable teaching and learning tool in education institutions. This particular example is said to have been used by students and staff in chemistry laboratories at Canterbury College during the mid-twentieth century.

During this period, automatic calculators were relatively standard as their main functions included basic arithmetic calculations – addition, subtraction, multiplication, and division. However, the physical design (as seen with this Friden STW-10 model) was more complex. Common features included two separate keyboards (the main keyboard to the right, and a smaller one to the left dedicated to multiplication calculations); over one hundred keys; manually adjustable decimal point indicators; two division keys and a moveable component that displayed calculation sums.

Like all technology, there were limitations to its capabilities. The Friden STW-10 model lacked function keys for complex calculations. For example, finding the square root of a number involved a tedious process of punching keys across the keyboard, with much room for error. Advanced functions, like the square root, were added during the late twentieth century. Much like the typewriter, the automatic calculator also created distractions within the classroom. With every punch of a key or processing calculation, this device created a loud mechanical click. It is assumed that this clicking would have eventually become background noise, much like the clicking of laptop keys in a classroom full of students, yet the automatic calculator was in no way a discrete teaching and learning device.