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April 8, 2015
p200 A mimeographed circular is generally tossed into the wastebasket without being read [what is that mimeograph smell? Levi probably could have told us. Probably it has something to do with aromatic compounds and “conjugated planar ring systems with delocalized pi electron clouds.”], but I realized immediately that this one did not deserve the common fate: it was an invitation to a dinner celebrating the twenty-fifth anniversary of our graduation from college. Its language got me to thinking: the addressee was treated to the intimate tu, and the amanuensis paraded a series of outdated student expressions, as if those twenty-five years had not passed. With involuntary comedy, the text concluded by saying, “. . . in an atmosphere of renewed comradeship, we will celebrate our silver wedding with Chemistry by telling each other the chemical events of our everyday life.” What chemical events? The precipitation of sterols in our fifty-year-old arteries? The equilibrium of membrane in our membranes?
p201 ...From the meager list that was left [of survivors from his class] a probable name popped up: Cerrato -- the honest, clumsy, eager Cerrato, to whom life had given so little and who had given so little to life. I had met him at intervals and fleetingly after the war, and he was an inert man, not shipwrecked: a shipwrecked man is he who departs and sinks, who sets himself a goal, does not reach it, and suffers because of it; Cerrato had never set himself anything, he had not exposed himself to anything, he had remained safely shut up in his house, and certainly must have clung to the “golden” years of his studies since all his other years had been years of lead.
Faced by the prospect of that dinner I had a two-sided reaction: it was not a neutral event, it attracted and repelled me at the same time, like a magnet brought close to a compass. I wanted to go and I didn’t want to... I wanted to go because it flattered me to compare myself to and feel myself more available than the others, less tied to money and the common idols, less duped, less worn out. I did not want to go because I did not want to be the same age as the others, that is, my age: I didn’t want to see wrinkles, white hair, didn’t want to count how many we were, nor count the absent, nor go in for calculations.
And yet Cerrato aroused my curiosity. At times we had studied together: he was serious and had no indulgence for himself, he studied without inspiration and without joy (he did not seem to know joy), successively boring through the chapters of the texts like a miner in a tunnel. He had not been compromised by Fascism, and he had reacted well to the reagent of the racial laws. He had been an opaque but reliable boy in whom one could trust: and experience teaches us that just this, trustworthiness, is the most constant virtue, which is not acquired or lost with the years. One is born worthy of trust, with an open face and steady eyes, and remains such for life. He who is born contorted and lax remains that way: he who lies to you at six, lies to you at sixteen and sixty. The phenomenon is striking and explains how certain friendships and marriages survive for several decades, despite habit, boredom, and the wearing out of subjects of discussion: I was interested in verifying this through Cerrato...
One of the few things I regret about my nomadic childhood is that I did not get to observe how the children I grew up with did, or did not, change over time. During the time I was in school, every three or four years my stage was swept clear and re-populated by a fresh cast of characters. I don’t doubt that what Levi says here is true, but it would have been nice to be able to confirm it.
p202 ...I learned that he had always worked in photographic chemistry: ten years in Italy, four in Germany, then again in Italy. [Maybe I should have saved my photography bit for here. ] He had, yes, been the promoter of the dinner and the author of the letter of invitation. He was not ashamed to admit it; if I would allow him a professional metaphor, his years of study were his Technicolor, the remainder was black and white. As to the “events” ... they really interested him. His career had been rich in events, even if for the most part they had indeed only been in black and white: Was that true of mine too? Of course, I agreed: whether chemical or not, though in recent years the chemical events had prevailed, in frequency and intensity. They give you a sense of Nicht dazu gewachsen [not up to], of impotence, inadequacy, isn’t that so? They give you the impression of fighting an interminable war against an obtuse and slow-moving enemy, who, however, is fearful in terms of number and bulk; of losing all the battles, one after the other, year after year; and to salve your bruised pride you must be satisfied with the few occasions when you catch sight of a break in the enemy front and you pounce on it and administer a quick single blow.
I'm not sure I would give the same superiority to college vs working life, but I might say it about a particular job -- my time at the Apple Media Lab. It was definitely a highlight, though, as with school, most of the people I share that experience with like to bitch about it.
As for the last bit about "an interminable war against an obtuse and slow-moving enemy" that reminds me more of my current Greening career: Year after year people (and vendors!) seem unable to sort their trash -- or give a damn about sorting their trash -- at all the events we work. This is also true of life in the long run.
I see a flaw in this logic -- sorry Bernard Shaw: The pace of technological and cultural change today is such that people of different generations -- especially generations over a generation apart -- experience the world differently. The logic of an age cohort over three generations "behind" the moment is of a problematic value, no matter how well educated and knowledgeable and mentally sharp. I'm not saying their "wisdom" is worthless, but that its relevance has to be questioned. Skeptical? How many contemporary social problems (related to sexuality, drugs, and race, for example) will vanish -- or near enough -- when today's elderly simply have the good grace to die?
p203 Cerrato also knew this never-ending battle: he too had experienced the inadequacy of our preparation, and the need to make up for it with luck, intuition, stratagems, and a river of patience. I told him that I was in search of events, mine and those of others, which I wanted to put on display in a book, to see if I could convey to the layman the strong and bitter flavor of our trade, which is only a particular instance, a more strenuous version of the business of living... that in this book I would deliberately neglect the grand chemistry, the triumphant chemistry of colossal plants and dizzying output, because this is collective work and therefore anonymous. I was more interested in the stories of the solitary chemistry, unarmed and on foot, at the measure of man, which with few exceptions has been mine: but it has also been the chemistry of the founders, who did not work in teams but alone, surrounded by the indifference of their time, generally without profit, and who confronted matter without aids, with their brains and hands, reason and imagination.
I asked him if he would like to contribute to this book. If he would, he should tell me a story... it should be our kind of story, in which you thrash about in the dark for a week or a month, it seems that it will be dark forever, and you feel like throwing it all up and changing your trade; then in the dark you espy a glimmer, proceed groping in that direction, and the light grows, and finally order follows chaos... he told me a story of silver.
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I’m not going to relate this story in detail. Some X-ray paper develops a distinctive flaw but only after two months time. And it isn’t all the X-ray paper but only paper produced on a particular day of the week. They eventually trace the problem to contaminated lint off overalls washed in a stream after the tannery upstream dumps its tanning vats into the stream once a week.
I have to take issue with his claim about the inadequacy of their preparation for their career in Chemistry. As he's described it, his instructors did an excellent job of forcing the students to find solutions to problems. Education is always going to be in arrears of practice so the trick is to train students to adapt and to teach themselves. As far as the Social Security Administration is concerned, my work career consists of the years I spent programming in languages that did not exist when I was in university. I was taught Boolean Algebra and left to sort out the rest on my own.
I have to take issue with his claim about the inadequacy of their preparation for their career in Chemistry. As he's described it, his instructors did an excellent job of forcing the students to find solutions to problems. Education is always going to be in arrears of practice so the trick is to train students to adapt and to teach themselves. As far as the Social Security Administration is concerned, my work career consists of the years I spent programming in languages that did not exist when I was in university. I was taught Boolean Algebra and left to sort out the rest on my own.
p209 ... We ended up by going to the bar, where gradually we became sentimental and promised each other to renew a friendship that actually had never existed between us. We would keep in contact, and each of us would gather for the other more stories like this one, in which stolid matter manifests a cunning intent upon evil and obstruction, as if it revolted against the order dear to man: like those reckless outcasts, thirsting more for the ruination of others than for their own triumph, who in novels arrive from the ends of the earth to thwart the exploits of positive heroes.
This story of forensic chemistry, reminded me of my own adventures in bug hunting. I spent a good deal of my programming years either testing the software written by others or my own software. The worst cases were when I was working for Apple as we were often using developmental versions of Operating Systems as well as of the applications running on those OSs -- you never knew which level of code was causing the problem.
With software, problems don’t usually crop up after a period of time, but the equivalent (worst) case is the bug that only occurs occasionally. A bug that can be reproduced easily by following the same steps is usually pretty easy to kill, but if it only happens occasionally, and you can’t determine why, it can be difficult to be sure you’ve killed it once and for all.
I happen to enjoy testing -- it requires a skill set of mine that is not always appreciated: being rigorously methodical and fanatically persistent. I also have enjoyed managing testing teams putting my own code to the test. Normally I detest being the manager but these cases have been exceptions, perhaps because the testers were eager and I was able to encourage them to be determined discoverers of my faults.
Silver (Ag 47)
Silver has long been valued as a precious metal. More abundant than gold, silver metal has in many pre modern monetary systems functioned as coinable specie, sometimes even alongside gold. In addition, silver has numerous applications beyond currency, such as in solar panels, water filtration, jewelry and ornaments, high-value tableware and utensils (hence the term silverware), and also as an investment in the forms of coins and bullion. Silver is used industrially in electrical contacts and conductors, in specialized mirrors, window coatings and in catalysis of chemical reactions. Its compounds are used in photographic film and X-rays...”
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“Silver is produced during certain types of supernova explosions by nucleosynthesis from lighter elements through the r-process, a form of nuclear fusion that produces many elements heavier than iron, of which silver is one.[3]”
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“The electrical conductivity of silver is the highest of all metals, even higher than copper, but its greater cost has prevented it from being widely used in place of copper for electrical purposes. An exception to this is in radio-frequency engineering, particularly at VHF and higher frequencies, where silver plating is employed to improve electrical conductivity of parts, including wires. Silver also has the lowest contact resistance of any metal.[citation needed] During World War II in the US, 13,540 tons were used in the electromagnets used for enriching uranium, mainly because of the wartime shortage of copper.[7][8][9]
Pure silver has the highest thermal conductivity of any metal, although that of the nonmetal carbon in the form of diamond and superfluid helium II are higher.[citation needed]
Silver halides are photosensitive and are remarkable for their ability to record a latent image that can later be developed chemically. Silver is stable in pure air and water, but tarnishes when it is exposed to air or water containing ozone or hydrogen sulfide, the latter forming a black layer of silver sulfide which can be cleaned off with dilute hydrochloric acid.[10]”
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“Silver metal dissolves readily in nitric acid (HNO 3) to produce silver nitrate (AgNO 3), a transparent crystalline solid that is photosensitive and readily soluble in water. Silver nitrate is used as the starting point for the synthesis of many other silver compounds, as an antiseptic, and as a yellow stain for glass in stained glass. Silver metal does not react with sulfuric acid, which is used in jewelry-making to clean and remove copper oxide firescale from silver articles after silver soldering or annealing. Silver reacts readily with sulfur or hydrogen sulfide H 2S to produce silver sulfide, a dark-colored compound familiar as the tarnish on silver coins and other objects.”
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“Silver chloride (AgCl) is precipitated from solutions of silver nitrate in the presence of chloride ions, and the other silver halides used in the manufacture of photographic emulsions are made in the same way, using bromide or iodide salts. Silver chloride is used in glass electrodes for pH testing and potentiometric measurement, and as a transparent cement for glass. Silver iodide has been used in attempts to seed clouds to produce rain.[10] Silver halides are highly insoluble in aqueous solutions and are used in gravimetric analytical methods.
Silver oxide (Ag 2O), produced when silver nitrate solutions are treated with a base, is used as a positive electrode (anode) in watch batteries. Silver carbonate (Ag 2CO 3) is precipitated when silver nitrate is treated with sodium carbonate (Na 2CO 3).[17]”
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“Latent images formed in silver halide crystals are developed by treatment with alkaline solutions of reducing agents such as hydroquinone, metol (4-(methylamino) phenol sulfate) or ascorbate, which reduce the exposed halide to silver metal. Alkaline solutions of silver nitrate can be reduced to silver metal by reducing sugars such as glucose, and this reaction is used to silver glass mirrors and the interior of glass Christmas ornaments. Silver halides are soluble in solutions of sodium thiosulfate (Na 2S 2O 3) which is used as a photographic fixer, to remove excess silver halide from photographic emulsions after image development.[17]”
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“The use of silver in photography, in the form of silver nitrate and silver halides, has rapidly declined due to the lower demand for consumer color film from the advent of digital technology. From the peak global demand for photographic silver in 1999 (267,000,000 troy ounces or 8304.6 metric tonnes) the market had contracted almost 70% by 2013.[31]”
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“The medical uses of silver include its incorporation into wound dressings, and its use as an antibiotic coating in medical devices. Wound dressings containing silver sulfadiazine or silver nanomaterials may be used to treat external infections. Silver is also used in some medical applications, such as urinary catheters and endotracheal breathing tubes, where there is tentative evidence that it is effective in reducing catheter-related urinary tract infections and ventilator-associated pneumonia respectively.[42][43] The silver ion(Ag+) is bioactive and in sufficient concentration readily kills bacteria in vitro. Silver and silver nanoparticles are used as an antimicrobial in a variety of industrial, healthcare and domestic applications.[44]” -Wiki
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