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:
“[T]he asphaltum contains an exactly requisite amount of sulphides for production of rubber tires. This brown material also contains “ichthyol,” a medicinal preparation used externally, in Webster’s clarifying phrase, “as an alterant and discutient.””
—State of Utah, U.S. public relief program (1935-1943)
“Man’s characteristic privilege is that the bond he accepts is not physical but moral; that is, social. He is governed not by a material environment brutally imposed on him, but by a conscience superior to his own, the superiority of which he feels. Because the greater, better part of his existence transcends the body, he escapes the body’s yoke, but is subject to that of society.”
—Emile Durkheim (1858–1917)
“It is difficult to generalize why so many Latino/as moved toward conservative ... views.... for many, I believe it is basically a matter of desiring material acquisitions. It is difficult to maintain a collective ideology in a society where possessions and power-status equal self-worth.”
—Ana Castillo (b. 1953)