Cogmakers

In middle school, I had a trio of teachers who were all in their first or second year of teaching.  Filled with youthful enthusiasm, they let us do things like sauté mushrooms over a Bunsen burner. They also let us play games, mostly review games, but still games.

Probably one of the only facts I retained from 8^th grade science was a trick for remembering the difference between latitude and longitude that came up during one review game, mostly because it resulted in not only my cheeks, but my whole entire scalp, face, and neck blushing bright red. In middle school my hair was long enough to get caught in the metal rivets in the seat backs. To demonstrate longitude, the teacher pointed at me and said,"See, the lines go up and down like her long hair."

I haven’t given much thought to longitude since putting down my pencil on the last science test I took. However when faced with the challenge to read a nonfiction book about technology, I was intrigued by a book called Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time by Dava Sobel.

“The measurement of longitude meridians…is tempered by time.” Seems straightforward enough until you remember that before the 1700s, there wasn’t a reliable time keeper that could be taken to sea.

By 1714, this problem of calculating longitude had become so pressing that a reward was being offered to the one who could solve it. Various methods were considered: lunar distance, magnetic compasses, signal boats at sea, and yes, wounded dogs.

Enter English clock maker John Harrison. Harrison succeeded in developing, over the course of his lifetime, several clocks that proved seaworthy - clocks that ship navigators know as chronometers.

Sobel sets out this curious history in a readable, fascinating, dare I say, page-turner. Not once did I feel compelled to blush.