The international standard kilogram, a cylinder-shaped hunk of metal that defines the fundamental unit of mass, has gained tens of micrograms of mass from surface contamination, according to a study. We create relics of standards to measure and value our world. A kilogram, a meter, north, south, a hole in ice to count back in time; fixed points that act as references and building blocks for many thoughts, acts and theories that construct our reality. These standards need to be spot on but they rarely are.This is a very comforting thought.
0:Jane Cain, the voice of the speaking clock, remembers making the first recordings:The actual recording wasn’t nearly as strenuous as most people seem to think… The real work was done by the engineers of the Post Office, who had a wonderful place up at Dollis Hill, where they took the recordings and played about with filmstrip and the like. The way I recorded it was in jerks as it were. I said: “At the Third Stroke” (that does for all the times), and then I counted from One, Two, Three, Four, for the hours, we even went as far as twenty-four, in case the twenty-four hour clock should need to be used, and then I said “…and ten seconds, and twenty seconds, and thirty, forty, fifty seconds”, and “o’clock” and “precisely”. The famous “precisely”. So what you hear is “At the Third Stroke it will be one, twenty-one and forty seconds”.
1: The first seismograph. The inventor was Zhang Heng, a famous scientist in the Eastern Han Dynasty Zhang Heng studied diligently, and was especially fond of astronomy, calendar and mathematics. The instrument was cast with eight dragons on the surface and each dragon had a copper ball in the mouth. On the ground below the dragons there were eight copper toads raising their heads and opening their mouths opposite the dragons’ mouths. The inner side of the seismograph was mysteriously constructed and contained quicksilver: when an earthquake occurred, the dragon facing that direction would open its mouth, and the ball would fall into the toad’s mouth, automatically indicating the direction of the earthquake.
2: Unknown (Egyptian)
Mason’s level and square amulet.
Amulets were personal adornments worn by the living and placed on mummy wrappings to provide protection and aid on the journey from death to the Afterlife. The color, shape, and other qualities of the materials were believed to endow the amulet and its wearer with special powers and protections. This amulet is one part of what was normally a two-amulet set: the mason’s square and plumb-line. This is the plumb-line; the real life object would have a length of cord with a weight at the end, hanging from the center. A plumb-line was used to check verticality. The mason’s square takes an “L” shape, used to measure right-angles. These amulets would ensure integrity and moral uprightness as well as emotional equilibrium.
3: The first compass was a spoon made of lodestone on top of a bronze plate. The lines spreading out from the spoon show the directions. The handle always pointed south instead of north.
5: The international prototype kilogram is a cylinder of platinum and platinum-iridium alloy, which is kept at the International Bureau of Weights and Measures (BIPM) near Paris. The kilogram may need to go on a diet. The international standard, a cylinder-shaped hunk of metal that defines the fundamental unit of mass, has gained tens of micrograms of mass from surface contamination, according to a new study. As a result, each country that has one of these standard masses has a slightly different definition of the kilogram, which could throw off science experiments that require very precise weight measurements or international trade in highly restricted items that are restricted by weight, such as radioactive materials. But ozone and ultraviolet light could be used to clean the kilograms without damaging them, the research suggests.
6:Located on the left of the entrance of the french Ministère de la Justice : 13 place Vendôme Paris 1st arr.)
7:The base unit of time is the second, defined as about 9 thousand million periods of radiation from the caesium atom. Historically units of time were defined by the movements of astronomical objects. The image shows Hafele and Keating aboard a commercial airliner, with two of the atomic clocks and a stewardess. (Stewardess ironically checking her wristwatch while standing behind the instrument), The Hafele–Keating experiment was a test of the theory of relativity. In October 1971, Joseph C. Hafele, a physicist, and Richard E. Keating, an astronomer, took four cesium-beam atomic clocks aboard commercial airliners. They flew twice around the world, first eastward, then westward, and compared the clocks against others that remained at the United States Naval Observatory. When reunited, the three sets of clocks were found to disagree with one another, and their differences were consistent with the predictions of special and general relativity.
9: “Metrologists, have come up with several suggestions to redefine the kilogram. One proposal, pushed by an international team called the Avogadro Project, aims to define the kilogram in terms of a specific number of silicon atoms. Just how many? That’s where the newly created silicon spheres come in. To determine the volume of each sphere, they will use optical interferometers to measure its width from 60,000 different points on its surface. Meanwhile, X-ray crystallographers will take pictures of the silicon crystal structure to determine the spacing and density of the atoms. By multiplying volume by density, each group should produce its own count of how many silicon atoms make up a kilogram. The important thing is for those numbers to agree with each other.”
10: A monetary system in which the standard economic unit of account is based on a fixed quantity of gold. Two golden 20 coins from the Scandinavian Monetary Union, which was based on a gold standard. The coin to the left is Swedish and the right one is Danish.
11: The nanotube material, named Vantablack, has been grown on sheets of aluminum foil by the Newhaven-based company. While the sheets may be crumpled into miniature hills and valleys, this landscape disappears on areas covered by it. “You expect to see the hills and all you can see … it’s like black, like a hole, like there’s nothing there. It just looks so strange,” said Ben Jensen, the firm’s chief technical officer.
13: Credit: Mark Twickler, University of New Hampshire/National Oceanic and Atmospheric Administration Paleoclimatology Program/Department of Commerce. Note: Access to ice-core samples was provided by the National Science Foundation.
14: A large microwave horn antenna that was used as a radio telescope during the 1960s at Bell Telephone Laboratories in Holmdel Township, Monmouth County, New Jersey, United States.
15:Clarence R. Carpenter at Doi Dao (north of Chiengmai, Thailand) in 1937, with the parabolic reflector which was used for making the first sound-recordings of wild gibbons (from Carpenter, 1940, p. 26).
Website Lotte Geeven.