…"it is my hope, as well as belief, that these my Labours will be no more comparable to the Productions of many other Natural Philosophers, who are now every where busie about greater things; then my little Objects are to be compar'd to the greater and more beautiful Works of Nature, A Flea, a Mite, a Gnat, to an Horse, an Elephant, or a Lyon.”—Robert Hooke at the end of his 28-page preface to Micrographia1 (1665)
I’ve written elsewhere in this blog about Robert Hooke, and
how, if there had somehow and impossibly been no Newton
What I’d like to talk about right now, though, of the many things to talk about concerning Robert Hooke, is the most iconographic image he ever produced, and perhaps one of the most famous scientific images of the 17th century—the flea.
The 28-year old Hooke published the results in a gorgeous and revolutionary book, Micrographia (a lovely e-text edition appears at Gutenberg, here) in 1665, which became an instant best seller and highly praised and valued. (Samuel Pepys, perhaps among the shiniest stars whose imprimatur was like a royal blessing, said the book (was) "the most ingenious book that I ever read in my life.") There is no telling what the people of the mid-17th century thought of seeing such incredible discoveries in the little semi-invisible stuff that made up their normal, daily lives. The only thing that somewhat equates to this would be if the first images of the Hubble were those of Earth-bound objects whose detail had previously been unknown. Hooke’s observations and drawings of things like the common flea were just an astonishment—that such a creature of “low order” could have such intricate detail and design was a complete revelation. The drawings of the fly's eye, too, was an inescapable wonder, an incredible object to consider as having any detail pre-microscope, and then revealed to have unimaginable design and elegance.
It turns out that the flea was not the most important object
that Hooke had in mind with the Micrographic—it
was part of an overall attempt at making sense of all creation, the bug part of
the book occupying only a part of the (only) one-fifth of the book’s 246 pages
devoted to living creatures. The book
actually starts with inanimate objects (the needle, followed by a razor, linen, silk, glass canes, flint, and so on), and then works it way through living
stuff, ending up talking about light and the Moon and the cosmos.
The opening images of the book are actually of the edge of a razor and the head of a needle—under magnification they showed a bitter, ragged edge and a nubby, pitted point (respectively)—which would have been almost as unimaginable and shocking as the flea….except that the flea of course opened possibilities of entire worlds of things alive in our semi-invisible environment. Things really weren’t as they seemed to be.
Hooke’s flea, as spectacular and revolutionary as it was,
was only a part of the story—the rest of the behind-the-picture narrative lies
in a much wider and more complex view of all things, living and not,
in which Hooke tells us we should employ the microscope/macroscope to solve disputes in our “wandring senses”. Not bad advice at all.
In the preface to the Micrographia Hooke states:
Thus all the uncertainty, and mistakes of humane actions, proceed either from the narrowness and wandring of our Senses, from the slipperiness or delusion of our Memory, from the confinement or rashness of our Understanding, so that 'tis no wonder, that our power over natural causes and effects is so slowly improv'd, seeing we are not only to contend with the obscurity and difficulty of the things whereon we work and think, but even the forces of our own minds conspire to betray us.
These being the dangers in the process of humane Reason, the remedies of them all can only proceed from the real, the mechanical, the experimental Philosophy, which has this advantage over the Philosophy of discourse and disputation, that whereas that chiefly aims at the subtilty of its Deductions and Conclusions, without much regard to the first ground-work, which ought to be well laid on the Sense and Memory; so this intends the right ordering of them all, and the making them serviceable to each other…
He continues with a short outline of how to accomplish this:
The first thing to be undertaken in this weighty work, is a watchfulness over the failings and an inlargement of the dominion, of the Senses.
To which end it is requisite, first, That there should be a scrupulous choice, and a strict examination, of the reality, constancy, and certainty of the Particulars that we admit: This is the first rise whereon truth is to begin, and here the most severe, and most impartial diligence, must be imployed; the storing up of all, without any regard to evidence or use, will only tend to darkness and confusion. We must not therefore esteem the riches of our Philosophical treasure by the number only, but chiefly by the weight; the most vulgar Instances are not to be neglected, but above all, the most instructive are to be entertain'd; the footsteps of Nature are to be trac'd, not only in her ordinary course, but when she seems to be put to her shifts, to make many doublings and turnings, and to use some kind of art in indeavouring to avoid our discovery.
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 in the whole Universe it self.1. The full title of the book: MICROGRAPHIA, OR,