Quote of the Day (Galileo, on His Re-Invention of the Telescope)

“You must know then that about two months ago a report was spread here that in Flanders a spy-glass [telescope] had been presented to Prince Maurice, so ingeniously constructed that it made the most distant objects appear quite near, so that a man could be seen quite plainly at a distance of 2 miles. This result seemed to me so extraordinary that it set me thinking. As it appeared to me that it depended upon the laws of perspective, I reflected on the manner of constructing it, and was at length so entirely successful that I made a telescope which far surpasses the report of the Flanders one. As the news had reached Venice that I had made such an instrument, six days ago I was summoned before their Highnesses, the Signoria, and exhibited it to them, to the astonishment of the whole senate. Many of the nobles and senators, although of a great age, mounted more than once to the top of the highest church tower in Venice, in order to see sails and shipping that were so far off that, without my spy-glass, it was two hours before they were seen steering full sail into the harbor; for the effect of my instrument is such that it makes an object 50 miles off appear as large as if it were only five.”—Galileo Galilei, in a letter to his brother-in-law Luca Landucci, August 29, 1609

As his letter indicates, Galileo didn’t invent the telescope (the unnamed man of Flanders was an optician named Johannes Lippershey). But the instrument that he ingeniously constructed on his own, then applied to a vastly different use—studying the heavens—dramatically reshaped the world, the relationship between science and religion, and his own life.

I’ve been itching to write about Galileo for awhile now. Reading some of his better-known works in college, for a course called Contemporary Civilization, was more fun than I expected for a work of science. You got a sense not only of what the man discovered, but of himself—of why he was interested in these particular phenomena, as well as of a combative streak that came out even when he tried to disguise it—a quality, of course, that got him in trouble.

You also get something of the flavor of the man in this letter talking about the beginning of his greatest scientific achievements. He not only reports about his marvelous new instrument—that it can make an object appear far closer than before—but also its impact (“to the astonishment of the whole senate”). The note of pride is impossible to ignore.

In the above quote, there’s an important phrase that one mentally translates into “telescope,” but that we should consider as it was originally written and meant: “spy-glass.” I can’t say that I would have noticed this without considering the chapter on Galileo in Jacob Bronowski’s coffee-table companion to his 1973 PBS series, The Ascent of Man.

Galileo grew to manhood in the closing years of the Renaissance, and I think he should be seen in the same light as earlier figures from that period of Italian history such as Leonardo and Michelangelo—as a multi-talented figure who had the potential to create things of practical value, including military designs.

This was of enormous value in Venice, not only to maintain its position as the informal capital of the capitalist culture struggling to be born at the time, but also to maintain its standing among the city-states on the Italian peninsula. Galileo had already worked on what he called a “Military Compass,” which was really akin to the modern slide-rule, printed and promoted a manual for it, and sold the whole shebang out of his own workshop.

So, back to “spy-glass.” Obviously, that would be great for catching glimpses of far-off vessels that could threaten Venetian supremacy of the seas. To me, anyway, the “astonishment” of the senators takes on an added dimension: the telescope was not only a fascinating curio but also a military intelligence breakthrough.

Galileo communicated such infectious, almost childlike, excitement about the telescope that he seemed unaware he’d moved into a dangerous new orbit for which all his studies in “natural philosophy” (as he called science then) couldn’t prepare him: politics.

The Venetian Senate was so excited about his discovery that they gave him a life professorship with an annual salary of one thousand florins. But then the Grand Duke of Florence, a former pupil of Galileo’s, topped that—not only matching the salary but freeing him from teaching.

Galileo elected to take the offer from Florence—as any college professor worth his salt would do today. But in the process he had made enemies of the Venetian Senate, which felt badly used.

In the vicious court politics of Italy of the time—which, Bronowski reminds us, also gave rise to Shakespeare’s Othello, the Moor of Venice—the first modern scientist could ill-afford foes who scrutinized his every word for a slip-up, with even more care than he had used in peering through his new telescope.