About ten months ago [1609] a report reached my ears that a certain Fleming [Hans Lippershey] had constructed a spyglass, by means of which visible objects, though very distant from the eye of the observer, were distinctly seen as if nearby... Of this truly remarkable effect several experiences were related, to which some persons gave credence while others denied them. A few days later the report was confirmed to me in a letter from a noble Frenchman at Paris, Jacques Badovere, which caused me to apply myself wholeheartedly to enquire into the means by which I might arrive at the invention of a similar instrument. This I did shortly afterwards, my basis being the theory of refraction. First I prepared a tube of lead, at the ends of which I fitted two glass lenses, both plane on one side while on the other side one was spherically convex and the other concave.

Astronomy is a cold, desert science, with all its pompous figures,—depends a little too much on the glass-grinder, too little on the mind. 'T is of no use to show us more planets and systems. We know already what matter is, and more or less of it does not signify.

But notwithstanding these Arguments are so convictive and demonstrative, its marvellous to see how some Popish Authors (Jesuites especially) strain their wits to defend their Pagan Master Aristotle his Principles. Bullialdus speaks of a Florentine Physitian, that all the Friends he had could ever perswade him once to view the Heavens through a Telescope, and he gave that reason for his refusal, because he was afraid that then his Eyes would make him stagger concerning the truth of Aristotle's Principles, which he was resolved he would not call into question. It were well, if these Men had as great veneration for the Scripture as they have, for Aristotles (if indeed they be his) absurd Books de cælo Sed de his satis.
(Indicating a belief that the Roman Catholic church impeded the development of modern science.)

By night the Glass
Of Galileo ... observes
Imagin'd Land and Regions in the Moon.

Computer science is no more about computers than astronomy is about telescopes, biology is about microscopes or chemistry is about beakers and test tubes. Science is not about tools. It is about how we use them, and what we find out when we do.

I have looked further into space than any human being did before me.
Having identified Uranus (1781), the first planet discovered since antiquity.

I therefore concluded, and decided unhesitatingly, that there are three stars in the heavens moving about Jupiter, as Venus and Mercury about the Sun; which at length was established as clear as daylight by numerous other observations.
Referring to his pioneering telescope observations.

It is impossible not to feel stirred at the thought of the emotions of man at certain historic moments of adventure and discovery—Columbus when he first saw the Western shore, Pizarro when he stared at the Pacific Ocean, Franklin when the electric spark came from the string of his kite, Galileo when he first turned his telescope to the heavens. Such moments are also granted to students in the abstract regions of thought, and high among them must be placed the morning when Descartes lay in bed and invented the method of co-ordinate geometry.

Just as a physicist has to examine the telescope and galvanometer with which he is working; has to get a clear conception of what he can attain with them, and how they may deceive him; so, too, it seemed to me necessary to investigate likewise the capabilities of our power of thought.

Looking through the telescope, one saw a circle of deep blue and the little round planet swimming in the field. It seemed such a little thing, so bright and small and still, faintly marked with transverse stripes, and slightly flattened from the perfect round. But so little it was, so silvery warm—a pin’s-head of light! It was as if it quivered, but really this was the telescope vibrating with the activity of the clockwork that kept the planet in view.
As I watched, the planet seemed to grow larger and smaller and to advance and recede, but that was simply that my eye was tired. Forty millions of miles it was from us—more than forty millions of miles of void. Few people realise the immensity of vacancy in which the dust of the material universe swims.

Many of the nobles and senators, although of great age, mounted more than once to the top of the highest church in Venice, in order to see sails and shipping … so far off that it was two hours before they were seen without my spy-glass …, for the effect of my instrument is such that it makes an object fifty miles off appear as large as if it were only five miles away. ... The Senate, knowing the way in which I had served it for seventeen years at Padua, ... ordered my election to the professorship for life.

O telescope, instrument of knowledge, more precious than any sceptre.

Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century. The conclusion is that astrophysics is too important to be left in the hands of astrophysicists who have gotten their main knowledge from these textbooks. Earthbound and space telescope data must be treated by scientists who are familiar with laboratory and magnetospheric physics and circuit theory, and of course with modern plasma theory.
[Lamenting the traditional neglect of plasma physics]

Teleology is a lady without whom no biologist can live. Yet he is ashamed to show himself with her in public.

TELESCOPE, n. A device having a relation to the eye similar to that of the telephone to the ear, enabling distant objects to plague us with a multitude of needless details. Luckily it is unprovided with a bell summoning us to the sacrifice.

The lessons of science should be experimental also. The sight of a planet through a telescope is worth all the course on astronomy; the shock of the electric spark in the elbow outvalues all theories; the taste of the nitrous oxide, the firing of an artificial volcano, are better than volumes of chemistry.

The next care to be taken, in respect of the Senses, is a supplying of their infirmities with Instruments, and, as it were, the adding of artificial Organs to the natural; this in one of them has been of late years accomplisht with prodigious benefit to all sorts of useful knowledge, by the invention of Optical Glasses. By the means of Telescopes, there is nothing so far distant but may be represented to our view; and by the help of Microscopes, there is nothing so small, as to escape our inquiry; hence there is a new visible World discovered to the understanding. By this means the Heavens are open'd, and a vast number of new Stars, and new Motions, and new Productions appear in them, to which all the ancient Astronomers were utterly Strangers. By this the Earth it self, which lyes so neer us, under our feet, shews quite a new thing to us, and in every little particle of its matter, we now behold almost as great a variety of creatures as we were able before to reckon up on the whole Universe it self.

These instruments have play'd me so many tricks that I have at last found them out in many of their humours.
On the problems with telescopes.

What are they doing, examining last month's costs with a microscope when they should be surveying the horizon with a telescope?
[Acerbic comment about directors of Brunner Mond, where he worked.]

With increasing distance, our knowledge fades, and fades rapidly. Eventually, we reach the dim boundary—the utmost limits of our telescopes. There, we measure shadows, and we search among ghostly errors of measurement for landmarks that are scarcely more substantial. The search will continue. Not until the empirical resources are exhausted, need we pass on to the dreamy realms of speculation.