Consider the eighth category, which deals with stones. Wilkins divides them into the following classifications: ordinary (flint, gravel, slate); intermediate (marble, amber, coral); precious (pearl, opal); transparent (amethyst, sapphire); and insoluble (coal, clay, and arsenic). The ninth category is almost as alarming as the eighth. It reveals that metals can be imperfect (vermilion, quicksilver); artificial (bronze, brass); recremental (filings, rust); and natural (gold, tin, copper). The whale appears in the sixteenth category: it is a viviparous, oblong fish. These ambiguities, redundances, and deficiencies recall those attributed by Dr. Franz Kuhn to a certain Chinese encyclopedia entitled Celestial Emporium of Benevolent Knowledge. On those remote pages it is written that animals are divided into (a) those that belong to the Emperor, (b) embalmed ones, (c) those that are trained, (d) suckling pigs, (e) mermaids, (f) fabulous ones, (g) stray dogs, (h) those that are included in this classification, (i) those that tremble as if they were mad, (j) innumerable ones, (k) those drawn with a very fine camel's hair brush, (l) others, (m) those that have just broken a flower vase, (n) those that resemble flies from a distance.

I … decided that the challenge of starting with a completely clean slate and mapping out a program that would influence astronomy for fifty years was just more than I could turn down.

I am very fond of the oyster shell. It is humble and awkward and ugly. It is slate-colored and unsymmetrical. Its form is not primarily beautiful but functional. I make fun of its knobbiness. Sometimes I resent its burdens and excrescences. But its tireless adaptability and tenacity draw my astonished admiration and sometimes even my tears. And it is comfortable in its familiarity, its homeliness, like old garden gloves when have molded themselves perfectly to the shape of the hand.

So says the most ancient book of the Earth; thus it is written on its leaves of marble, lime, sand, slate, and clay: ... that our Earth has fashioned itself, from its chaos of substances and powers, through the animating warmth of the creative spirit, to a peculiar and original whole, by a series of preparatory revolutions, till at last the crown of its creation, the exquisite and tender creature man, was enabled to appear.

The book of Nature is the book of Fate. She turns the gigantic pages,—leaf after leaf,—never re-turning one. One leaf she lays down, a floor of granite; then a thousand ages, and a bed of slate; a thousand ages, and a measure of coal; a thousand ages, and a layer of marl and mud: vegetable forms appear; her first misshapen animals, zoophyte, trilobium, fish; then, saurians,—rude forms, in which she has only blocked her future statue, concealing under these unwieldy monsters the fine type of her coming king. The face of the planet cools and dries, the races meliorate, and man is born. But when a race has lived its term, it comes no more again.

You propound a complicated arithmetical problem: say cubing a number containing four digits. Give me a slate and half an hour’s time, and I can produce a wrong answer.