Thursday, August 26, 2010

Tools Of The Trade: Bring 'Em Near

In 1608 Hans Lippershey, a Dutch naturalist who had a nagging interest in the heavens, invented the telescope. It was a series of glass lenses set in a wooden tube that allowed Lippershey to gaze at the planets with fascination and wonder. This initial invention is what is known today as the “refracting telescope” and was quickly seized upon by Dutch mariners who passed the invention on to other Europeans. At this point, the tool became known as a “Dutch telescope”. With a little tinkering by Galileo, the telescope took off.

The uses of these first telescopes were different from the Hollywood vision. No lookout in the tops of a buccaneer ship was scanning the horizon for prey with his “bring ‘em near” pasted to his eye. Telescopes were expensive items and reserved, at first almost exclusively, for celestial navigation. This held true for navies and freebooters alike for the rest of the century. Should you ever be so unfortunate as to pick up a book that offers Laurens de Graff first seeing Veracruz through his telescope, for instance, my advice would be to put it down and back away. You don’t know where that story has been but it’s quite certain that it has never touched reality.

In 1666 Isaac Newton took up the project of improving the telescope. The problem with the original designs was the glass lenses. These caused what is known as spherical and chromatic aberration. Basically this amounts to something similar to the refraction that occurs when an object is looked at through water. Because of this, corrections had to be made in order to navigate using a telescope and an objects would look closer and off center in relation to their actual position. It was rather the seafaring equivalent of “objects in mirror are closer than they appear”.

Mirrors were, in fact, the way Newton solved the problem. To some degree, at least. Knowing that reflection did not cause chromatic aberration and that mirrors could focus light, Newton devised the “reflecting telescope” which used a combination of glass lenses and mirrors – most notably a mirror diagonal to the eyepiece – to correct for chromatic aberration. This “Newtonian telescope” was an improvement on the original but it was bulky and awkward, having to be mounted on a tripod for use. Its updated version, however, is still in use today.

But what of our mariners? The telescope one pictures in the sailor’s hand came into common use later in the 18th century. In 1765 Peter Dollond, building on the work of his father John Dollond, produced the triple objective telescope. Using Dollond’s design it was possible to build a brass tube that would collapse for storage and would utilize Newton’s reflective design. By the end of the century, telescopes could be carried in one’s pocket.

Sailing men of all stripes were using these handy telescopes by the 1780s. Many were reasonably priced, although the truly fine versions owned by the wealthy were almost more like jewelry than tools. The word “telescope” quickly went by the board at sea as well. Spy glass was used; glass was a more frequent term. Perspective was also used in English. The French called telescopes lunette d’approches (literally “access glasses”) shortened quickly to lunette. The Spanish called them vidrio de espía or simply d’espía.

The habit of spy glasses not being used for keeping an eye on the horizon continued. Despite their compact size and relative economy (compared to the originals) they were still expensive things and most often a keen and usually young set of eyes was more effect. Especially for sighting prey. Once something seen, an officer would take up his glass and determine who or what it might be. The perspective also came in handy when charting coastal areas, islands, inlets and so on.

On a final and perhaps disappointing note, La lunette was probably never referred to in reality as a “bring ‘em near”. Though it sounds colorful in a Treasure Island sort of context, it simply wasn’t language as it was actually spoken. Sorry mates; you’ll have to stick with glass.


Header picture: "No Prey No Pay" by Don Maitz from his 2006 Pirates! calendar.

2 comments:

Timmy! said...

Ahoy, Pauline! That does seem to be a rather large glass in the header picture too. Not that size matters or anything... Right, Pirate Queen?

Pauline said...

Ahoy, Timmy! Well, I've never known Mr. Maitz to use metaphor in his paintings... Oh wait. He does that all the time. I'm guessing the reference is not "accidental" :)