# Retrotechtacular: Pascal Got Frustrated at Tax Time, Too

While necessity is frequently the mother of invention, annoyance often comes into play as well. This was the case with [Blaise Pascal], who as a teenager was tasked with helping his father calculate the taxes owed by the citizens of Rouen, France. [Pascal] tired of moving the beads back and forth on his abacus and was sure that there was some easier way of counting all those livres, sols, and deniers. In the early 1640s, he devised a mechanical calculator that would come to be known by various names: Pascal’s calculator, arithmetic machine, and eventually, Pascaline.

The instrument is made up of input dials that are connected to output drums through a series of gears. Each digit of a number is entered on its own input dial. This is done by inserting a stylus between two spokes and turning the dial clockwise toward a metal stop, a bit like dialing on a rotary phone. The output is shown in a row of small windows across the top of the machine. Pascal made some fifty different prototypes of the Pascaline before he turned his focus toward philosophy. Some have more dials and corresponding output wheels than others, but the operation and mechanics are largely the same throughout the variations.

# Binary adder will give you slivers

A while back we looked at [Matthias’] one-pin dot matrix printer. Now we’re jumping over to his woodworking website to feast on his wooden binary adding machine. His creation uses glass marbles as the data for this device. A resolution of up to six bits can be set on the top of the adder, then dropped into the machine as one number. With each new drop, the number is added to the total stored in the machine. The device is limited to totals less than 64. If a larger number is enter, the device wraps around back to zero by dumping the 7th bit off the end. He’s even got a master clear that allows you to easily read the stored total and evacuate the “data” from the machine.

This has quite a few less wires than the last binary adder we looked at… wait, it has no wires! But we still love it. A physical representation of what is going on with binary math really helps grasp what the magic blue smoke inside those silicon chips is all about. Don’t miss his video walk through of the adding machine embedded after the break. Can’t get enough of marbles interacting with wood? He’s got a few more projects you might enjoy. Continue reading “Binary adder will give you slivers”