nzeldes 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
We all buy LED light bulbs these days (remember the days of CFL and tungsten filament bulbs?). And we buy them in little cardboard boxes made from dead trees. You have skinny single-bulb boxes, and you have twice as wide two-packs. So imagine my surprise when I saw the in-between box at the left in … Read more
Eating at a restaurant can be a romantic occasion, but restaurants seem to feel that justifies keeping a low lighting. Which is fine for romance but annoying when you need to peruse the menu. However, this one restaurant in Milano solved the problem! They had low enough lighting, but on each table they had this … 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
Here is one impressive calculating device: Washington Sabatini’s reinforced concrete calculator. This complicated circular slide rule is one of the largest items in my collection. It comprises ten concentric aluminum rings covered with complicated scales and pointers. The rings are all movable except for the second largest; that one is fixed to the body of … Read more
The photographic camera is one of the great inventions of the 19th century, and is quite a simple idea: take a light sensitive surface, put a lens in front of it, add the ability to control exposure time and aperture, and you’re all set. And for more than a century, that’s what cameras were all … 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
When my kids were at school they were taught addition with colored wooden rods. Well, a century earlier two innovative Frenchmen – Henri Genaille and Edouard Lucas – invented a system that does rapid multiplication and division using much more sophisticated rods, and I have in my collection a box of these ingenious calculation aids. … Read more
Monsieur C.-F. Martin was a retired naval clerk, and evidently he had developed a great love for painstaking calculation. Just see this 100×100 multiplication table and units conversion tables he published at the beginning of the 19th century, to help his countrymen deal with the switch from the old Empire weights and measures to the … Read more
