Lucky Dip

One of the wonders of the web is the fact that many old books, whose copyright has lapsed, are being put online. I often find myself looking through the contents of The Online Books Page in the hope of striking lucky. Today for example, I see that a PDF version of an astronomy book published in 1900 is now available: Essays in Astronomy by Ball, Harkness, Herschel, Huggins, Laplace, Mitchel, Proctor, Schiparelli, and Others (New York: D. Appleton and Company, 1900). This is terrific stuff. For example, there’s an essay by Lord Kelvin setting out what he can surmise, using the best available scientific knowledge of the time, about the age of the sun. He concludes:

Now, Lord Kelvin was a great scientist, who did important research in physics, and in particular, thermodynamics. Yet, science at that stage was only just begininng to uncover the workings of nuclear physics, and hence the mechanisms at work in the sun were unknown to him. His conclusions, made on the best evidence available to him at the time, were ultimately wrong.

 

There’s also an essay by Giovanni Schiaparelli on the planet Mars. The translation, from the original Italian, uses the word "canals" instead of Schiaparelli’s intended word "channels". Thus was a whole myth seeded about there being canals on Mars. 

 

20-20 hindsight is, of course, easy in retrospect. But then again these essays also show the scientific method in action. Working with the data available to them at the time, they formulated theories that made sense for their time. Subsequent new findings allowed new theories to arise that fitted the known facts better, and science moved on.