Material
While some hourglasses actually did use sand as the granular mixture to measure time, many did not use sand at all. The material used in most bulbs was a combination of "powdered marble, tin/lead oxides, and pulverized, burnt eggshell". Over time, different textures of granule matter were tested to see which gave the most constant flow within the bulbs. It was later discovered that for the perfect flow to be achieved the ratio of granule bead to the width of the bulb neck needed to be 1/12 or more but not greater than 1/2 the neck of the bulb.
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Famous quotes containing the word material:
“We soon saw, as he saw, that he was not to be pardoned or rescued by men. That would have been to disarm him, to restore to him a material weapon, a Sharp’s rifle, when he had taken up the sword of the spirit,—the sword with which he has really won his greatest and most memorable victories. Now he has not laid aside the sword of the spirit, for he is pure spirit himself, and his sword is pure spirit also.”
—Henry David Thoreau (1817–1862)
“This is the essential distinction—even opposition—between the painting and the film: the painting is composed subjectively, the film objectively. However highly we rate the function of the scenario writer—in actual practice it is rated very low—we must recognize that the film is not transposed directly and freely from the mind by means of a docile medium like paint, but must be cut piece-meal out of the lumbering material of the actual visible world.”
—Sir Herbert Read (1893–1968)
“Technological change defines the horizon of our material world as it shapes the limiting conditions of what is possible and what is barely imaginable. It erodes ... assumptions about the nature of our reality, the “pattern” in which we dwell, and lays open new choices.”
—Shoshana Zuboff (b. 1951)