Show & Tell...

Thought I'd change up the blog a bit... Here's a collection of related items:

This is an abacus.. The oldest known mechanical computation devices were based on some type of using beads to represent units.

This is a slide rule, also known as a "slip stick"... It's based on using logarithmic progressions to perform multiplication, division & trigonometric calculations. My teaching myself how to use one greatly enhanced my knowledge of mathematics.. Unfortunately, it was only accurate to two decimal places, at best.

This is one of the earliest commercial calculators available. Using a Light Emitting Diode display, it could perform simple mathematical calculations of addition, subtraction, multiplication and division.

This is the Texas Instruments TI-30-II, a second generation of the TI-30 "slide rule" calculator. Like it's predecessor, it had a range of functions beyond the simple arithmetic, including log functions, sine, cosine, converting values from radians into degrees, calculating squares and square roots. Note the Liquid Crystal display. By the time this calculator had been marketed, Hewlitt Packard had developed it's Graphic Display calculator, as well as it's alpha numeric programmable calculators...


I mentioned in a previous post, the incredible innovations that the 70's saw in consumer products, and how it possibly saved the economy at that time... This is also an example of that principle.