The History Of Zero

"Zero," on the common thermometer, like the fanoiful names of the constellations, is a curious instance of the way wise men's errors are made immortal by becoming popular. It may be worth while to say tlmt the word itself (zero) comes to na through the Spanish f rom the Arabic, and rneans empty, henee nothing. In expressions like "90 deg. Fahr. ," the abbreviation, Fahr. , stands for Fahrcnheit, a Prtissian merchant of Dantzic, ou the shores of the Baltic Sea. His Ml name was Gabriel Daniel Fahrenheit. From a boy he was a close observer of nature, and when only nineteen years old, in the remarkably cold winter of 1709, he experimented by putting Bnow and salt together, and noticed that itproduced a degree of cold oqual to the coldest day of that year. As tliat day was the coldest that the oldest inhabitant could remember, Gabriel was the more struck with tho coincidence of his little I scientific diseovery, and hastily I eluded that he had i'ound the lowest degree of temperature known in the world, i either natural or artificial. He callea : that degree zero, and constructed a : thermometer, or a rude weather glass, j with a scale graduated up from the zero to a boiling-point, which he numbered 212, and the freezing-point thirty-two. Because, as he thought, mercury contracted the thirty-second of its volume on being cooled down from the temperature of freezing water to zero ; and expandT ed 180fch on being heated from the j ing to the boiling point. Time showed that this arrangement, instead of being truly sciontific, was as arbitrary as the división of the Bible ! to verses and chapters, and-that these j two points no more represented the real extremes of temperature, than " from Dan to Beersheba " expressed the exact extremes of Palestine. But Fai'enheit's thermometer had been ! largely adopted, with its inconvenient scale ; and none thought of any better untü his name became an authority, for i Fahrenhcit finally abandoned trade and : gave himself to science. Then habit made people cling to the establishod scale, as habit makes the English cling ! to their old system of cumbrous fractional money. Onr nation began to use Fahrenheit's thermometer about the middle of the last century, or not far from the time when Old Style was exchanged for New ' Style in the writing of dates. The three countries wliich use Fahrenheit are Holland, England and America. Bussia and Germany use Keaumer's therj mometer, in which the boiling point is counted 80 degroes above freezing point. France uses the centrigrade thermometer, so called because it marks the boiling point 100 degrees from freezing ! point. On many accounts the centigrade system is the bijst, and the triumph of con: venience will be attained, when zero is made the freezing point, and when the boiling point is put 100 or 1,000 degrees i from it. and all the subdivisions are ii'd decimally. - If Fahrenheit had done this at first, or even if he had made it one of his many : improvements, after the public adopted i his error, the luck of opportunity, which was really his, would have secured to his i inven tion the patronage of the world. -