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:
“Science has done great things for us; it has also pushed us hopelessly back. For, not content with filling its own place, it has tried to supersede everything else. It has challenged the super-eminence of religion; it has turned all philosophy out of doors except that which clings to its skirts; it has thrown contempt on all learning that does not depend on it; and it has bribed the skeptics by giving us immense material comforts.”
—Katharine Fullerton Gerould (1879–1944)
“It may be possible to do without dancing entirely. Instances have been known of young people passing many, many months successively, without being at any ball of any description, and no material injury accrue either to body or mind; Mbut when a beginning is made—when felicities of rapid motion have once been, though slightly, felt—it must be a very heavy set that does not ask for more.”
—Jane Austen (1775–1817)
“A philistine is a full-grown person whose interests are of a material and commonplace nature, and whose mentality is formed of the stock ideas and conventional ideals of his or her group and time.”
—Vladimir Nabokov (1899–1977)