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« an astronomical year | Main | get the lead in »


The Romans also used lead acetate as a sweetener in wine. Was this another significant source of lead in their environment?

I would like top clarify the value of TetraEthyl Lead in the piston engine. TEL acts to prevent detonation of the fuel-air charge during combustion. Steady propagation of a flame front through the mixture until it is all burned takes place on a very short timescale to human perception, taking on the order of a portion of to several milliseconds or so.
During detonation, (or pinging or knocking, all words for varying degrees of the same phenomenon) the combustion process kicks up to propagate at the speed of sound, much faster than the speed of flame front propagation, or it spontaneously explodes.

Higher octane or performance number fuels, partially differentiated by blending of the hydrocarbon cocktail that is gasoline and by the addition of TEL are more resistant to this apparent “explosion” phenomenon, and permit higher overall compression ratios (either by the piston alone or by supercharge plus piston compression) As compression ratio is directly related to Otto cycle efficiency, higher is better. Normal combustion is smooth push, but detonation is an impact phenomenon, which can cause all sorts of havoc. A given engine can be made capable of more power from the same weight/volume if detonation phenomena can be suppressed to allow higher compression.

TEL doesn’t typically play a role in keeping a charge from starting to burn before intended, called pre-ignition, although when the combustion process runs amok, key elements of the combustion chamber particularly the spark plug electrodes, can suddenly become much hotter, bringing about pre-ignition. An aircraft piston engine suffering from heavy detonation may destroy itself in half a minute or so.

On a historical note, TEL and related fuel technology very possibly gave the Royal Air Force the slimmest of performance advantages over the Luftwaffe during the Battle of Britain, a contest that was in question to the very end. The US made enough 100+ octane fuel available to the RAF to give them a 10-15% (100-150 horsepower) advantage in combat. This technological edge increased throughout the conflict, and at the close of the war, the allies were utilizing plentiful fuel with octane/performance number as high as 115-145, while the Axis powers fought the war with ever tightening supplies of 87 octane fuel. Like all technology, this TEL has its obvious nobility and deviltry, depending on the moment, the issues and the circumstances.

Finally, today’s unleaded regular 87 octane automobile gas is largely the hydrocarbon cocktail developed for these WWII aviation fuels, without the TEL. Prior the development of these high performance fuels, gasoline blends without TEL were in the 70 octane range, and TEL was added to get to the mid 80’s.

This could easily become a CPP blog topic on its own. The value of various octane fuels to the motorist and a particular vehicle is not understood by the great majority of fuel and vehicle consumers, because it is complex and it is typically explained incorrectly.

Political note. When banning lead in gasoline came before congress in the 70's, the then Congressman GWH Bush voted against it. If the Ethyl company had prevailed, by now our grandchildren would have difficulty learning to tie their shoelaces.
Continuing in the grand Bush tradition, W Bush replaced the competent researchers on the Lead Advisory council with lobbyists for the lead paint industry . The acceptable levels of blood lead in children had been going down, and were supposed to go from 10 ppm to 5, but that stopped.There are still tens of thousands of inner city kids in the older cities poisoned with lead every year- lower iq's, more aggressive behavior

The impact of lead exposure is so destructive that I have devoted mysalf to raising awareness about its effects. I have co-authored a newly released book, “LEAD BABIES: Breaking the cycle of learning disabilities, declining IQ, ADHD, behavior problems, and autism,” The focus of the book is the explaination as to how lead is hurting our families. LEAD BABIES is an easy read; along with a fascinating scientific perspective, four powerful narratives tie science to everyday life. A comprehensive section describes lead’s “hiding” places in the kitchen, playroom, and medicine cabinet. LEAD BABIES is an important book. It empowers individuals to prevent their families from lead damage. Readers are given the tools to identify, reduce and remove lead from their own homes, routines and activities with a step-by-step lead inventory. As consumers, readers learn what to look for when buying new products.
For more information visit
Check our links page; we have a few blogs that contain regularly updated information about how to live a lead-smart life.

I didn't think that *any* alloy had a place on the periodic table....

The lead problem is mostly about lead paint in older buildings. Lead acetate- sugar of lead- is sweet and babies chew paint peelings. It is expensive to test children and test old buildings, and the enforcement program and remediation is spotty. So it is mostly an inner city problem.Older children dont absorb as much, and sources like pottery and toys are very scattered.

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    Physics Cocktails

    • Heavy G
      The perfect pick-me-up when gravity gets you down.
      2 oz Tequila
      2 oz Triple sec
      2 oz Rose's sweetened lime juice
      7-Up or Sprite
      Mix tequila, triple sec and lime juice in a shaker and pour into a margarita glass. (Salted rim and ice are optional.) Top off with 7-Up/Sprite and let the weight of the world lift off your shoulders.
    • Listening to the Drums of Feynman
      The perfect nightcap after a long day struggling with QED equations.
      1 oz dark rum
      1/2 oz light rum
      1 oz Tia Maria
      2 oz light cream
      Crushed ice
      1/8 tsp ground nutmeg
      In a shaker half-filled with ice, combine the dark and light rum, Tia Maria, and cream. Shake well. Strain into an old fashioned glass almost filled with crushed ice. Dust with the nutmeg, and serve. Bongos optional.
    • Combustible Edison
      Electrify your friends with amazing pyrotechnics!
      2 oz brandy
      1 oz Campari
      1 oz fresh lemon juice
      Combine Campari and lemon juice in shaker filled with cracked ice. Shake and strain into chilled cocktail glass. Heat brandy in chafing dish, then ignite and pour into glass. Cocktail Go BOOM! Plus, Fire = Pretty!
    • Hiroshima Bomber
      Dr. Strangelove's drink of choice.
      3/4 Triple sec
      1/4 oz Bailey's Irish Cream
      2-3 drops Grenadine
      Fill shot glass 3/4 with Triple Sec. Layer Bailey's on top. Drop Grenadine in center of shot; it should billow up like a mushroom cloud. Remember to "duck and cover."
    • Mad Scientist
      Any mad scientist will tell you that flames make drinking more fun. What good is science if no one gets hurt?
      1 oz Midori melon liqueur
      1-1/2 oz sour mix
      1 splash soda water
      151 proof rum
      Mix melon liqueur, sour mix and soda water with ice in shaker. Shake and strain into martini glass. Top with rum and ignite. Try to take over the world.
    • Laser Beam
      Warning: may result in amplified stimulated emission.
      1 oz Southern Comfort
      1/2 oz Amaretto
      1/2 oz sloe gin
      1/2 oz vodka
      1/2 oz Triple sec
      7 oz orange juice
      Combine all liquor in a full glass of ice. Shake well. Garnish with orange and cherry. Serve to attractive target of choice.
    • Quantum Theory
      Guaranteed to collapse your wave function:
      3/4 oz Rum
      1/2 oz Strega
      1/4 oz Grand Marnier
      2 oz Pineapple juice
      Fill with Sweet and sour
      Pour rum, strega and Grand Marnier into a collins glass. Add pineapple and fill with sweet and sour. Sip until all the day's super-positioned states disappear.
    • The Black Hole
      So called because after one of these, you have already passed the event horizon of inebriation.
      1 oz. Kahlua
      1 oz. vodka
      .5 oz. Cointreau or Triple Sec
      .5 oz. dark rum
      .5 oz. Amaretto
      Pour into an old-fashioned glass over (scant) ice. Stir gently. Watch time slow.