Monday, April 21, 2008

Cool!

A wooden adding machine -- how cool!





Here's the
website of the guy who designed and built this contraption.

4 comments:

Jerry said...

Cool!

But I wonder why he said things like: "4 plus 2 is 6 in Binary"?

Bob said...

Jerry--
In decimal the right-most digit is the ones, and to the left of that is the tens and then the hundreds. So the number 380 is three hundreds plus eight tens plus zero ones (or three-hundred plus eighty).

Similarly in binary the right digit is the ones, and to the left of that is the twos and then the fours digits. In binary the only values a digit can have are one or zero, so instead of saying the binary number "110" is one four plus one two plus zero ones, it's just easier to say it's "four plus two" which (when expressed in decimal) is "six".

Jerry said...

I fully understand how the binary system works, but it just sounded strange to hear him describe it in that way. In my field, binary numbers are always presented as 10110, 11011, etc., just like hex numbers are presented as 0BADF00D, 626F62, etc.

The fact that he had labeled his device for the decimal user made his addition of the word "binary" seem a little strange. The device was nothing more than a standard flip-flop calculator, with labeling that the "normal" word could understand.

Bob said...

But Jerry, normal people think in decimal, so saying the binary number "110" is one-one-zero is nonsense --- "110" just the plain old number six written in a funny way.

(Hex is just perverse -- like cross-breeding birds with mammals.)