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    Re: Experience with an artifical horizon
    From: Gary LaPook
    Date: 2020 Oct 18, 15:26 -0700

    From: David Iwancio
    Date: 2020 Oct 18, 10:07 -0700

    Re:  used motor oil

    Part of getting "used" means picking up some rather nasty stuff both as combustion byproducts and from engine wear, including heavy metals.  It's stuff that typically goes out the exhaust pipe, but some doesn't make it that far and instead gets collected and concentrated over the useful life of the oil.

    I'd guess it's safer than undiluted mercury, but that's not a very high hurdle in my opinion.

    (Heck, I used long-life synthetics just so I can deal with the stuff less often.)


    Mercury is not hazardous when used in an artificial horizon outdoors. You can even drink the stuff! But avoid breathing in the vapors over a long period of time. The "Mad Hatter" breathed such fumes for many years working with mercury in the production of hats. 

    I'll bet when you were a kid your mom used Mercurochrome anticeptic on your cuts, you didn't die from those many exposures to mercury, did you? That anticeptic is still available worldwide except in the U.S.

    So keep it in a tightly sealed bottle.

    Don't store that bottle in your bedroom but, to be really careful, store it outside or in the garage. 

    Carefully poor it into and out of your dish with a funnel slowly to avoid spilling any which you don't want to do anyway because it is expensive. Do this outside.

    If you do spill some inside make sure you get it all up, it is tricky, it's not called quicksilver for nothing. Keep that room ventilated for a good long while to dissapate any vapors if some of the quicksilver couldn't be picked up and possibly disappeared down into cracks, it will continue to evaporate until it is all gone. It can be dangerous in that situation so just be careful in its use. 


    "Elemental mercury[edit]

    Quicksilver (liquid metallic mercury) is poorly absorbed by ingestion and skin contact. Its vapor is the most hazardous form. Animal data indicate less than 0.01% of ingested mercury is absorbed through the intact gastrointestinal tract, though it may not be true for individuals suffering from ileus. Cases of systemic toxicity from accidental swallowing are rare, and attempted suicide via intravenous injection does not appear to result in systemic toxicity,[27] though it still causes damage by physically blocking blood vessels both at the site of injection and the lungs. Though not studied quantitatively, the physical properties of liquid elemental mercury limit its absorption through intact skin and in light of its very low absorption rate from the gastrointestinal tract, skin absorption would not be high.[34] Some mercury vapor is absorbed dermally, but uptake by this route is only about 1% of that by inhalation.[35]

    In humans, approximately 80% of inhaled mercury vapor is absorbed via the respiratory tract, where it enters the circulatory system and is distributed throughout the body.[36] Chronic exposure by inhalation, even at low concentrations in the range 0.7–42 μg/m3, has been shown in case–control studies to cause effects such as tremors, impaired cognitive skills, and sleep disturbance in workers.[37][38]"


    But while mercury is generally considered highly poisonous, doctors in the late 19th century gave patients significant amounts of the element to treat intestinal obstructions.

    "Drinking mercury has a laxative effect," explains the toxicologist Gebel. "Its density cleans the intestine wonderfully."

    The effect is completely different when mercury is inhaled. As a vapor, the mercury is inhaled as individual atoms and quickly absorbed by the lungs where its poisonous effects begin to develop.

    If, however, you drink mercury, hardly any of it stays in the system - most of it exits the body once it has performed its function.

    "Taken orally, without inhaling, there's almost no risk," says Gebel.


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