Tales Told in Lead

Every metal marks a romantic chapter in human history.

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As a result of their affinity for silver, lead deposits were eagerly sought in ancient times. The Greek mines at Laurium operating well before 3000 B.C. and the mines of the Iberian Peninsula beginning during the Iron Age are both celebrated for their contributions to the wealth of nations. Likewise, ancient Persian kings owed their legendary wealth to abundant lead/silver deposits. A breakthrough for extracting silver from lead ores, called cupellation, appeared around 3500 B.C. and greatly enhanced the popularity of silver. By the third millennium B.C., silver taken from lead ore had become the chief unit of exchange in the Near East, and the technology rapidly spread to other parts of the Old World. Cupellation remained the dominant process for silver recovery for nearly 5000 years, an important consideration in using archived lead in bogs and other deposits for paleoenvironmental detective work. By my estimate, annual production was about 160, 900, 11,000, 32,000, and 6000 metric tons during the Copper, Bronze, Iron, Roman, and Barbaric ages, respectively. Total production to 1000 A.D. is estimated at 32 million tons. Singer estimated that about 134 million tons of lead was discovered in the Old World throughout recorded history. Thus, about 24% of the discovered lead reserves were mined in ancient times, a more reasonable figure than previous higher rates.

Progress in lead. Logarithmic plot of historical lead production over time.
Progress in lead. Logarithmic plot of historical lead production over time.

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Another arena for massive growth was in the production of coinage   Duncan-Jones reckoned that by the middle of the second century there were 7000 million HS of silver coins in circulation, which was roughly four times my estimate of the volume of Roman coins in circulation in the middle of the last century ВСЕ.   And the volume of Roman coinage had already grown ten times in the century before that   Perhaps.  But confirmation of the huge volume of Roman silver-lead mining (silver was produced by cupellation as a by product of lead-mining) comes impressively from an apparently incontrovertible source

I refer of course to the Greenland Icecap, and the peat bogs or lake sediments of Sweden, Switzerland and Spain.   A whole series of recent studies from a variety of sites have shown with remarkable concordance that the volume of wind-borne contaminants from smelting mineral ores reached a significant peak in the Roman period.   Hong and associates showed that lead pollution from systematic samples of the Greenland icecap, datable to between 500 ВСЕ and 300 CE, reached densities four times the natural (i.e. prehistoric) levels.  Renberget aL showed that lead contamination in a wide assortment of sediments from southern Swedish lakes reached a peak in or around the first century CE. Shotyk et aL showed from a study of a Swiss peat bog that there was a huge upsurge in lead pollution from the first century ВСЕ to the third century CE, when pollution (and presumably production) began to decline.

There seems little doubt among these investigators that the main source of contamination in this period was lead smelting and cupellation for silver and copper in the Roman empire, and particularly Spain.  Hong and associates showed that copper production in the world rose sevenfold in the last five centuries ВСЕ, continued at a high but reducing level in the first five centuries CE and then fell sevenfold to reach a trough in the thirteenth century. Once again they are convinced that classical civilizations, and in particular the Roman empire was the major source of this wind-borne pollution.

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"If it works, why change it?"

Russian space culture thinks in centuries. Baikonur, the original home of the Soviet space program, now belongs to Kazakhstan, but Russia rents it from Kazakhstan on a hundred-year lease, as Britain in the old days rented Hong Kong from China. The lease still has eighty years to run, and Baikonur feels like a Russian town. Historical relics of Russian space activities are carefully preserved and displayed in museums. The three patron saints are the schoolteacher Konstantin Tsiolkovsky, who worked out the mathematics of interplanetary rocketry in the nineteenth century; the engineer Sergei Korolev, who built the first orbiting spacecraft; and the cosmonaut Yuri Gagarin, who first orbited Earth. Korolev and Gagarin lived side by side in Baikonur in simple homes, which are open to the public. In a public square is a full-scale model of the Soyuz launcher that Korolev designed. It is a simple, rugged design and has changed very little since he designed it. It has the best safety record of all existing launchers for human passengers. The Russian space culture says, "If it works, why change it?"

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In Solem el Lunam.

metal symbols alchemy - into Sun and Moon. This use of planetary signs to designate metals dates from the infancy of alchemy. The Liber de mineralibus (III, i, 6; Borgnet ed., V), attributed to Albertus Magnus, gives the reasons for the planetary names of the metals. The Jammy (1651) and the Borgnet (1898) editions of the Alchimia frequently employ: Sol for gold, Luna for silver Venus for copper, Mercury for mercury, Saturn for lead, Jupiter for tin. When the planetary name is used in the Borgnet edition, the present translation capitalizes the name of the metal; for example, Venus is translated as Copper, but cuprum as copper. On the planetary designation of metals, see J. R. Partington, "Report of Discussion upon Chemical and Alchemical Symbolism, Ambix, I (1937), 61; and Pearl Kibre. "The Alkimia minor Ascribed to Albertus Magnus," Isis, XXXII (2) (June, 1949), 270. [Even more interesting than the replacement of the true names of the metals by those of the planets is the fact that the symbols representing the planets came to represent the metals, just as "we write H for an atom of hydrogen, [and] К for an atom of potassium,. . ."(F. Sherwood Taylor, The Alchemists [New York: Schuman, 1949]. p. 51). This convenient shorthand goes back to the earliest Greek alchemical manuscripts, dating from around A.D. 250. "We have considerable lists of the signs in the oldest Greek manuscripts. Some of them are derived from the signs of the planet with which the metals were associated, others from the pictorial representations of the things symbolized, others from the initial letters of the name.

"The connection of the planets and metals is certainly ancient, and it persists throughout the whole of alchemy.

"The metals have all received planetary signs. Gold receiving the sign ..., representing the sun; silver the sign of the waxing moon ...; mercury that of the waning moon ... (Hermes speaks of "that which drips from the waning moon"); copper has the sign of Venus (Aphrodite-Isis-Hathor) ♀ ; lead has the sign of Saturn ...; iron has the sign of Mars ♂. There remain the signs of electrum and tin. Tin has in these old lists the symbol of Hermes, and electrum that of Zeus. In later times (between 500 and 700 A.D.) the symbol of Hermes was given to mercury in place of that of the waning moon. Electrum was no longer considered a separate metal, and its symbol was then given to tin.

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The Appian Way

The map of the Appian Way The world's first all-weather road system was built to facilitate modern warfare. Following their defeat in the Samnite Wars, particularly their humiliation at the Battle of the Caudine Forks along the rocky Apennines in 321 BC, the Roman military began to develop more effective attack formations and better transportation routes through uneven terrain. The formation, the legion, allowed troops to scatter when facing troublesome roads, then reunite easily when conditions improved. The improved transportation route was the Via Appia, or AppianWay.

The Roman censor Appius C laudius Caecus ordered construction of the Appian Way, a paved road uniting Rome and Capua, to be usable by troops in all weather. Begun in 312 BC, the road was built of multiple layers of durable materials, the top layer composed of a mixture of concrete, rubble, and stones set in mortar. The road was instrumental in facilitating Roman victory in future wars with the Samnites.

Equally important was the Appian Way's vatious political uses. It was ctucial to building commercial interests and sustaining cultural links with and poIitical control over the provinces. Over time, several roads were built to link Rome with other cities and colonies, including the Via Flaminia (Flaminian Way), which headed north to link Italy with the Latin colony of Ariminum. In aII, the Roman road system covered more than fifty thousand miles and crossed through thirty countries. Only remnants of the roads still exist.

The Appian Way today

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The last of wine

The earliest inventions - fire, baws and arrows, wheeled carts - are the most difficult to place in time. New excavations and methods of analysis can overthrow the hoariest of received opinions on who invented what when. A case in point is the first manufacture of wine.

The last of wine For a long time, the earliest aidence of wine manufacture came from Egypt from about 3000 B.C. Then, in 1991, Canadian graduate student Virginia Badler made a new claim about a dirty fragment of pottery from a Sumerian site in western lran dating from about 3500 B.C. The interior of the pottery, housed at the Royal Ontario Museum, was stained red. Some archaeologists thought it was paint; Badler thought it was wine.

Chemists at the University of Pennsylvania put the issue to the test by analyzing the reddish residue with infrared spectroscory, a method that distinguishes chemicals by the wavelengths of light they absorb. They found that the residue was rich in tannic acid, an organic substance found almost without exception in grapes. Badler was proven right and the date for the invention of wine was pushed back five hundred years.

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Райский радиотелескоп

Райский радиотелескоп

ALTAIR on the island of Roi Namur by beningh

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Gramma versus Computer, Round 1

gramma-- Okay, this time you get to do it all by yourself. Turn on the computer.
-- No, that's the keyboard.
-- Those are the speakers. Yes, I know you know that.
-- No, gramma, that's the mouse.
-- Of course you'll understand this! Just not all at once. No, that's the monitor, and you've already turned it on.
-- Gramma, you've tried to turn on everything but one.
-- That big box by your right knee, gramma.
-- Yeah, I kinda figured you'd forgotten about it, too.

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Grandma's Computer

Author Unknown

Grandma's ComputerIn the not too distant past
I remember very well -
Grandma's tended to their knitting,
and their cookies were just swell.

They were always at the ready,
when you needed some advice.
And their sewing (I can tell you)
Was available - and nice.

Well, Grandma's not deserted you.
She dearly loves you still.
You just won't find her cooking,
but she's right there at the till.

She thinks about you daily,
you haven't been forsook.
Your photos are quite handy,
in her Pentium notebook.

She scans your art work now though,
and combines it with cool sounds,
to make electronic greetings.
She prints pictures by the pounds.

She's right there when you need her -
you really aren't alone.
She's out now with her "puter" pals,
but she took her new cell phone.

You can also leave a message
on her answering machine.
Or page her at the fun meet.
She's been there since nine fifteen.

Yes, the world's a very different place,
there is no doubt of that.
So "E" her from her web page,
or join her in a chat.

She's joined the electronic age,
and it really seems to suit her.
So don't expect the same old gal,
cause Grandma's gone "Computer".

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А звезды падали…

Наблюдение падающих звезд с воздушного шара

Наблюдение падающих звезд с воздушного шара – иллюстрация из книги "Travels in the Air", 1871, by James Glaisher.

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Harvard Engineers Build Tiny Processors out of Nanowires

Today in the journal Nature, researchers led by Charles Lieber report a big step forward in the field of tiny computing: the creation of linked-up logic circuits made of nanowires, which could be used to build itty-bitty processors.

The devices described in the paper layer additional wires across the germanium-silicon ones; charges can be trapped in these wires, influencing the behavior of the underlying nanowires. This charge trapping is nonvolatile but reversible; in other words, you can switch one of the nanowires on or off by altering the charge stored in its neighborhood. This makes it possible to turn the nanowires into a standard field-effect transistor (the authors term them NWFETs for “nanowire field-effect transistors”). [Ars Technica]

Lieber had been able to create simple versions of those NWFETs before, but those were difficult to build on a large enough scale to create logic circuits.

Lieber’s team reports in this week’s Nature that they’ve been able to build a programmable array of nanowires that can have up to eight distinct logic gates. They dub such an array a “logic tile,” with the idea that multiple tiles could be connected to perform more-complex logic functions. [IEEE Spectrum]

Though Lieber’s achievement is impressive, he concedes that it’s difficult to imagine his tech competing with the incredible pace at which computer processing speed accelerates. But, he says, he doesn’t have to: Nanoscale processors have qualities that could make them more suitable than traditional ones for the very small devices that are on the leading edge of research.

“The key thing is to recognize that we’re not trying to compete directly with high-performance silicon electronics,” he says. Projections show that the new wires could be up to 100 times more energy efficient than conventional technologies. That could make the meshes useful as logic circuits in low-power applications such as small robots, or perhaps biomedical devices. [Nature]

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