how was the first peridoc table made?
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"Mendeleev's key insight in devising the periodic table was to lay out the elements to illustrate recurring ("periodic") chemical properties (even if this meant some of them were not in mass order), and to leave gaps for "missing" elements. Mendeleev used his table to predict the properties of these "missing elements", and many of them were indeed discovered and fitted the predictions well."
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You could call it an icosahedron, but I have never heard it called that since I think it is easier to just say 20-sided die.
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use Eulers formula\n\nF+ V = E+2\n\nhere F = faces = 8\nV = vertices =12\nE = edges = 18\n\ntherefore it is possible to construct the solid.\n\nit is a hexagonal cylinder
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An abacus is a calculation tool, often constructed as a wooden frame with beads sliding on wires. It was in use centuries before the adoption of the written Hindu-Arabic numeral system and is still widely used by merchants and clerks in the People's Republic of China, Japan, Africa, and elsewhere.\n\nThe plural of abacus is abaci.\nThe origins of the abacus are disputed, as many different cultures have been known to have used similar tools. It is known to have existed in Babylonia and in China, with invention to have taken place between 1000 BCE and 500 BCE. The first abacus was almost certainly based on a flat stone covered with sand or dust. Lines were drawn in the sand and pebbles used to aid calculations. From this, a variety of abaci were developed; the most popular were based on the bi-quinary system, using a combination of two bases (base-2 and base-5) to represent decimal numbers.\n\nFOR MORE INFORMATION PL. VISIT:\nhttp://en.wikipedia.org/wiki/Abacus
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Build an abacus.  \nArrange 10 beads on a piece of piano wire.  Every fifth bead should be a different collor.\n--oo--oo0-oooo0--\nMake a few more strings and mount them together in parallel or inline with each other.\n------ooooxoooox\nooo----oxoooox--\n--ooooxoo----ooo\n\nA really cool math based model would be a display of geometric shapes.\n\nYou could go to the matherworld site and print out some patterns for the platonic solids.  Then cut them out and fold them together.  The collection can be displayed in a couple of ways.  The easiest would be to mount them on straws poking out from a block of styrofoam.  The most dramatic would be to arrange them to hang in a mobile.  If you want instructions on making a mobile, send an email to samphelps at yahoo.\n\nPlatonic solids are the 3 dimensional shapes where all the sides are the same.  The most familiar is a cube where each side is a square.  Another is the tetrahedron where each side is a triangle.
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Try this link.\nhttp://www.chennaionline.com/artscene/craftpalace/history/handicrafts.asp
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These tables give a guide
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Look here for the tables:\n\nhttp://wulfenite.fandm.edu/Data%20/Table_7b.html\n\nhttp://wulfenite.fandm.edu/Data%20/Table_7a.html\n\nThe values you need are in the second link.
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You mean 'Swarovski' and technically (if it's clear), it's just cut glass and would have said conductance properties. If it's colored, they probably used some additive, maybe lead, so it might be moreso.
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The umbrella was invented over four thousand years ago - there is evidence of umbrellas in the ancient art and artifacts of Egypt Assyria Greece and China\n\nThe early European umbrellas were made of wood or whalebone and covered with alpaca or oiled canvas. The artisans made the curved handles for the umbrellas out of hard woods like ebony, and were well paid for their efforts.
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Probably silicone and iron.   It's a friggin big rock.   Hollow it out a bit; near the center the gravity is probably near earths gravity.
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The Dioptra was another surveying instrument that was utilized by Roman Surveyors.  It was used to measure horizontal and vertical angles and could also be used as a leveling instrument and for astronomical observations as well.  As with most instruments used by the surveyors of the Roman Empire, the Dioptra was not an original invention of the Romans, but was developed by the Greeks and implemented by the Romans.  There are very few remains of the Dioptra and the estimation of the replication of this instrument vary from reference to reference.  The best recollection of the description of what the Dioptra may have looked like and its uses comes from the records of Hero of Alexandria.  Hero, a Greek, described the use of the Dioptra, however many of the important details regarding the construction of the instrument were either lost or destroyed.  Since there has not been any concrete evidence to the contrary, it is believed that the Romans used the Dioptra in much the same way as the Greeks did and the design of the Roman Dioptra was parallel to that of the Greek origin.\n\nThe staff of the Dioptra may have been a three-legged instrument, similar to today's tripod or possibly a monopole with three points at the base to assist in keeping it vertical.  Either of these types of staffs were approximately the equivalent of 7-7 U.S. Survey Feet in height.  At the top of the staff, was a circular plate with a cylinder attached to it.  This plate and cylinder allowed for rotation.  At the top of the cylinder was another circular plate, approximately 30 inches in diameter.  This plate was made of wood and was divided and marked into 360 degrees.  Although the Dioptra was divided into degrees, it is believed that these measurements were mainly used for astronomical observations.  However, the Greeks and Romans did have the knowledge and ability to use trigonometry, so it is possible that they used the Dioptra for horizontal angle measurement as well.\n\nAnother instrument used for leveling that could be placed on the tripod or monopole instead of the Dioptra was the water level.  This instrument was a linear bar made of wood and was approximately the equivalent of 6-7 U.S. Survey Feet in length, 1-1/2 inches thick and 2 inches in width.  In the center of the instrument, a groove was cut.  A vertical metal tube would be placed in the groove and the ends of the tube would protrude upwards approximately 1-1/2 inches from each end of the wooden bar.  A flat bar placed over the metal tube would assist in keeping the tube firmly in place.  In each end piece of the tubing, a glass cylinder would be fitted.  This cylinder was approximately the same height as the metal tube.  The glass cylindrical tube would be filled with water.  At the base of each end piece, a revolving rod or screw would be placed.  These screws would be used to move the instrument up or down until the surveyor determined it to be level.\n\nAn alternative method of leveling implemented by Roman Surveyors was by using an instrument call a Chorobate.  Since this instrument was made primarily of wood, there are virtually no remains still in existence today.  However, the descriptions for the design of the Chorobate and its use have been recovered.  It is believed that the Chorobate was used mainly for leveling in aqueducts.  Because of its massive size and weight, it would not have been as practical and appropriate as the Dioptra in laying out roadways.\n\nThe Chorobate was approximately 20 Roman Feet in length and was made predominantly of wood.  The Chorobate was elevated from the ground by wooden supports approximately 1-2 Roman Feet in height.  At the base of the supports were wooden braces, which had vertical marks across the face.  Plumb lines were hung from the supports and when the plumb lines on each end of the Chorobate touched the respective vertical marks simultaneously, the instrument would be level.  In windy conditions, a different method for using the Chorob
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The discovery of glass\nNatural glass has existed since the beginnings of time, formed when certain types of rocks melt as a result of high-temperature phenomena such as volcanic eruptions, lightning strikes or the impact of meteorites, and then cool and solidify rapidly. Stone-age man is believed to have used cutting tools made of obsidian (a natural glass of volcanic origin also known as hyalopsite, Iceland agate, or mountain mahogany) and tektites (naturally-formed glasses of extraterrestrial or other origin, also referred to as obsidianites).\n\nAccording to the ancient-Roman historian Pliny (AD 23-79), Phoenician merchants transporting stone actually discovered glass (or rather became aware of its existence accidentally) in the region of Syria around 5000 BC. Pliny tells how the merchants, after landing, rested cooking pots on blocks of nitrate placed by their fire. With the intense heat of the fire, the blocks eventually melted and mixed with the sand of the beach to form an opaque liquid.\n\nThis brief history looks, however, at the origins and evolution of man-made glass.\n\n5000 BC - A craft is born\nThe earliest man-made glass objects, mainly non-transparent glass beads, are thought to date back to around 3500 BC, with finds in Egypt and Eastern Mesopotamia. In the third millennium, in central Mesopotamia, the basic raw materials of glass were being used principally to produce glazes on pots and vases. The discovery may have been coincidental, with calciferous sand finding its way into an overheated kiln and combining with soda to form a coloured glaze on the ceramics. It was then, above all, Phoenician merchants and sailors who spread this new art along the coasts of the Mediterranean.\n\n3500 BC - The oldest fragments of glass vases (evidence of the origins of the hollow glass industry), however, date back to the 16th century BC and were found in Mesopotamia. Hollow glass production was also evolving around this time in Egypt, and there is evidence of other ancient glassmaking activities emerging independently in Mycenae (Greece), China and North Tyrol.\n\n16th century BC - Early hollow glass production\nAfter 1500 BC, Egyptian craftsmen are known to have begun developing a method for producing glass pots by dipping a core mould of compacted sand into molten glass and then turning the mould so that molten glass adhered to it. While still soft, the glass-covered mould could then be rolled on a slab of stone in order to smooth or decorate it. The earliest examples of Egyptian glassware are three vases bearing the name of the Pharaoh Thoutmosis III (1504-1450 BC), who brought glassmakers to Egypt as prisoners following a successful military campaign in Asia.\n\n1500 BC - There is little evidence of further evolution until the 9th century BC, when glassmaking revived in Mesopotamia. Over the following 500 years, glass production centred on Alessandria, from where it is thought to have spread to Italy.\n\n9th century BC - The first glassmaking "manual" dates back to around 650 BC. Instructions on how to make glass are contained in tablets from the library of the Assyrian king Ashurbanipal (669-626 BC).\n\n650 BC - Starting to blow\nA major breakthrough in glassmaking was the discovery of glassblowing some time between 27 BC and AD 14, attributed to Syrian craftsmen from the Sidon-Babylon area. The long thin metal tube used in the blowing process has changed very little since then. In the last century BC, the ancient Romans then began blowing glass inside moulds, greatly increasing the variety of shapes possible for hollow glass items.\n\n27 BC-AD 14 - The Roman connection\nThe Romans also did much to spread glassmaking technology. With its conquests, trade relations, road building, and effective political and economical administration, the Roman Empire created the conditions for the flourishing of glassworks across western Europe and the Mediterranean. During the reign of the emperor Augustus, glass objects be
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http://educate-yourself.org/fe/fejoewatercell.shtml\nI'm unsure of anything that describes how to really make one.\nThis site tries, but it's rather goofy to follow. Maybe you'll have better luck that I would.
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See page 32 of the PowerPoint presentation at http://www.ccm.udel.edu/Personnel/homepage/class_web/Lecture%20Notes/2004/AskelandPhuleNotes-CH10Printable.ppt,\n\nA number of PDFs are found with the following search http://www.google.com/search?hl=en&lr=&q=pb+sn+eutectic+photomicrograph&btnG=Search
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I don't think anyone has truly answered your question yet. You're question, as best as I can tell, deals with compression. Now, perhaps you might be able to see it better with a big foam brick. The book pushes down on the foam, until it won't compress anymore and then the book stops sinking. Well, the table is technically the same way, but its already super packed. The molecules of the table, be they the atoms of wood, or glass, or whatever your table is made of, are a network of atoms, all interlocked in a solid form by opposing charges. By placing the book on top, you cause the atoms to become closer, which in turn increases the repulsion of the atoms. Gravity pulls down, Electric (Magnetic) Resistance pushes back.
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If you don't count the abacus, which is ancient, then Blaise Pascal invented the first mechanical computation machine in France in 1642. Check it yo!\n\nhttp://www.thocp.net/hardware/pascaline.htm