Very true. In the "covered wagon" days, it was a common practise to put a silver coin (usually a "cartwheel" - $1) into the milk pitcher - this kept it fresh throughout the day without benefit of refrigeration.
An interesting line of search to pursue is "colloidal silver" - which is enjoying a re-emergence in health circles. It has also shown excellent results when used in bandages for large-area burns - the gauze to be next to the burned skin is soaked is a solution of colloidal silver (susp.), which encourages healing, prevents infection, and also reduces scarring.
Colloidal silver, taken orally in small amounts, has also shown significant benefits to overall health.
As I recall, one of the better writeups on "how and why" appeared on the site for Ford's More Than Military (
www.fordsmtm.com, if memory serves,) along with generators and supplies. Worth looking into - if for no more than academic interest.
I'd not heard of nickel being used as a sacrifical anode - have you a source I could check? Every time I've heard of nickel being used in conjunction with corrosion reduction/elimination, it's always been as a protective coating (electroless nickel being preferred over nickel electroplate, due to the fact that electroless nickel presents a more uniform coating thickness.)
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