Standing on the Shoulders of Predecessors

It's often said that, in science, one advance is built on another. In technology or inventions, it's also true that one advance depends on one or more prior inventions.

Movies, for example, were built on the previous invention of photography, but with the new addition of the idea that, if you took a series of photographs and showed them in rapid sequence, you could produce the illusion of motion. So the camera (and film) had to exist, and then what was new was the idea of a camera that could take rapid, sequential photos—and a machine (projector) to show the movies. And that of course also needed a light source, and it was not Edison's incandescent light bulb that was used but an arc lamp, which was brighter. (A similar arc lamp was used to light the movie sets.)

Television, of course, drew upon several prior inventions. First there was the concept of creating a "moving picture" by breaking a scene down into a succession of still frames projected and viewed in rapid sequence—as in the movies.

Also there was the idea of wireless transmission, from radio; and the idea of the camera. Plus, the cathode ray tube, which had been invented several decades earlier, and the notion of creating an image on the screen of that tube by building it up with a sequence of lines which in turn were made up of dots.

Plus, again, the camera. But this time the camera had to create an image that was broken down into lines and dots—the reverse of how the TV image was created on the TV receiver's screen.

And now the television set using a cathode ray tube is pretty much obsolete because the TV sets using LCD and plasma displays (which evidently have come to be called "flat-screen" TV sets) are actually cheaper to make.

Copyright © 2012 by Richard Stein

Invented by Whom, Where, When?

The other day I happened to hear about the invention of the garbage disposal. Also at around the same time I heard about when the first automatic washer came on the market, and the first hermetically sealed refrigerator—these latter two a little before my time.

I was somewhat astonished to realize that I had never thought about when the garbage disposal was invented. It's one of those things that you take for granted.

Of course what you are aware of as an innovation within your own lifetime, and what you take for granted, depends on your age.

Children today—well, probably anyone under about 30—have always known computers, so they don't even think about a time when home computers didn't exist. And cell phones are only a bit more recent so kids take them for granted, too, and have no notion that they didn't always exist.

In my family, some fairly well-off relations got some gadgets at a time when they were not yet really common: the automatic washer, air conditioning, even TV. My own family was the third one on our block to get TV, in December 1950. My grandparents, aunt and uncle, and several of my friends already had it in their homes. Everyone wanted one—of course it was something of a status symbol—even though we had one channel, and there was no 24-hour broadcasting, so when there was no program we actually stared at the "test pattern" on the screen. I suppose it sounds like some third-world country but it really was just a smallish city in Pennsylvania.

Copyright © 2011 by Richard Stein