I was riding an elevator in a public building, and on its wall I saw the amazing control panel shown here. It had a large number, presumably the floor we were on, and it had two arrays of numbers, one on a screen and one in a keypad. I’m still not sure what the idea … Read more
Was trying to get to my plane at Dulles International airport in Washington, DC. There are a number of terminals, and a train connecting them. So we got on the train, expecting it to do the usual thing – run in a (topological) circle, or maybe back and forth along a line, between the terminals … Read more
Lately the electrical system in my home got in the habit of shutting down unexpectedly. This did not happen by some faulty appliance tripping a fuse; we soon found that it was the Ground Fault Circuit Interrupter (GFCI, that anti-electrocution safety device) that was deciding to trip, but when we reset it the power stayed … Read more
The humble clothespin is a ubiquitous item that has been with us for generations; and it is simple enough that you’d think it’s reached the point if utmost reliability. And yet, it seems that it is in fact very unreliable: clothespins break, they fall apart, they need constant replenishing… but I seemed to remember that … Read more
See this water tap. Now when you want to turn it on, what do you do? What I did, is grab the handle and try to turn it anti clockwise, around its vertical axis. And nothing happened, it refused to budge. Here’s how you turn the water on with this tap: You see, it has … Read more
Here are two boxes of vitamins I take, separated by a few months in production time, newer version on the right. Same product, one change: The original version is marked “Age 50+“, denoting the people it’s optimized for: those aged 50 and above (“+”). The new version is marked “SLVR+“. After some thought I figured … Read more
Here is a screenshot from my Lenovo ThinkPad computer. The computer was running a self-test using the incorporated Lenovo utility, and I tried to abort this test by exiting that utility. And then I got this dialog box: Read it carefully: If you continue, all the tasks … will be canceled. Are you sure? And … Read more
The Tavernier-Gravet company was France’s premier scientific instrument maker at the end of the 19th century, and it stayed abreast of the latest developments in slide rule design and production when it entered the 20th century. In this this new article on my History-of–Computing site I illustrate some of their problems and solutions as they … Read more
A few years ago I sighted on eBay a set of three German circular slide rules of the Controller brand. There was a big one, 20 cm in diameter; a midsized one 11 cm across; and a small one at 7.5 cm. They all looked pretty much the same except for their sizes, and this … Read more
I was at this coffee shop and saw the two machinettas. Of course I didn’t buy one – as coffee lovers, we have all the machinettas we need at home – but I did notice how the pair represents two different solutions to a small but important design bug that the classic machinetta had subjected … Read more
