The decades around the turn of the 20th Century were a time of technological change that is hard to appreciate even when reading about it on the screen of a smartphone. In a relative eyeblink, the world went from whale-oil lanterns and horsedrawn carriages to electric light and automobiles. Telephones, automobiles, radio, powered flight: A seemingly endless stream of inventions were changing the landscape of the world, and among those dazzling gadgets were self-loading firearms. Maxim guns were starring in the tales of colonial wars and, with the development of early self-loading pistols, anybody could have this kind of H.G. Wells technology right in their pocket!When I got started in the computer business 30 years ago I made an effort to learn all I could about the hardware I was using: what all the pins on all the connectors were for, how to set all the jumpers, and how to program all the chips. I suppose that worked out okay for me but I soon got tired of it because I discovered that as soon as I had mastered something it was no longer useful for me to know anything about it. Either it had become obsolete, or the company had changed direction, or I had changed companies. After a while it got to the point where I only bothered to look up what I absolutely needed to know in order to get the job done.
From reading Patrick O'Brian's stories about the British Navy during the Napoleonic Wars (round about 1800) I got the impression that technological progress up till then had been rather slow. Everything was staid, conservative "we've been doing it this way for a thousand years and we ain't gonna change on account of the whim of some whippersnapper".
Then I came across this little bit in Neal Stephenson's The System of the World:
This was a very large and curious device. Note the man standing to the left of the brick pillar. There is no wheel and no crank, it just has a piston in a cylinder hanging on on one end of the beam and the pump hanging on the other. And it is not steam power that does the work of lifting the water. The atmosphere does the work. The steam serves only to raise the piston in the cylinder, and so lower the pump rod to take on a new load of water. When the piston has been raised (that is the position shown in the drawing), cold water is sprayed into the cylinder which causes the steam to condense, which forms a partial vacuum and the air pressure from the atmosphere pushes down on the piston, and so raises the pump rod and its' load of water. It must have been horribly inefficient, yet it still worked well enough that it got the job done. The water was pumped out of the mines, and the miners were able to extract ore. Even with the low pressures they must have been using, they still had trouble building boilers that would not explode. I suspect the problem was simply that the boilers were large. Since pressure is measured in force per unit area, it follows that a larger boiler with a larger surface area is going to be subject to larger overall forces.
Steam power is only 300 years old. That is not a very long time given what we know of the history of civilization.
Quoting Wikipedia :
ReplyDeleteThe first device that may be classified as a reaction steam turbine was little more than a toy, the classic Aeolipile, described in the 1st century by Greek mathematician Hero of Alexandria in Roman Egypt.[3][4][5] In 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit. Steam turbines were also described by the Italian Giovanni Branca (1629)[6] and John Wilkins in England (1648).[7] The devices described by al-Din and Wilkins are today known as steam jacks.