Fellas: A friend of mine has requested I post this particular question. His dad was a black smith, and told him about this method to treat metal to a silvery finish. It involved what he called "the bark of an ash tree" which is burnt, and the ash mixed with hot water. Apply it to the metal, and you get this silvery finish.
Has anyone ever heard of that, or something similar?

No, but it sounds like a good explanantion as to why they're called "Ash" trees. Interesting.

RSY

Sounds interesting, here is my take on it-

To make sodium hydroxide in the old days water was percolated through wood ashes repeatedly. When the water was dense enough an egg would float in it, it was cooked with lard to make soap. Nowadays the only way this is useful is if you are dirty in camp and don't have soap, the white ash from a fire and water can clean OK, but then you have to wash the ash off too.

Anyway, back to the question- what you are making then is a weak sodium hydroxide paste, which I suppose would be a distant cousin to the german boiling sodium hydroxide method of finishing. I also do know that the bark of a tree makes more ash than the wood does, dunno if that makes a difference at all, or if it has to be an ash.

Did his dad say if the metal was supposed to be hot? If you post more maybe next time I have my forge fired up I'll try it, lord knows I have plenty of ash trees around here.

Hey Mark, being a home soap maker I've got to stick my nose in here. What's being made by leaching wood ashes is mostly potassium carbonate, though it has lots of other things in it. It's called "potash" because, well, you make it from ashes in a pot. Potassium was the name given to the metal in potash. Potassium carbonate, like sodium carbonate, is a strong base and will saponify fats nicely. Potassium soaps are very soft and the homemade soap was kept in a barrel, a scoop being taken out whenever needed. The term "soft soap" came from this. Since poor farmers could make their own, it was low status stuff compared to the hard lye (sodium) soap made by the candlemakers or chandlers in town. You had to have money to buy that, though! It was very hard to get a repeatable concentration of the base in potash solutions, and the soap could be either very greasy (good for the skin) or caustic enough to take your hide off!

Matt, this sounds like a precursory treatment I used to use to give character and personality to black powder parts prior to browning and or blueing.

I did a quick Google on the subject, came back with this http://www.finishing.com/Letters/index.html#1b which was much more than I wanted, but the interesting thing I did note was the concerns for the disposal of the product after use.

Something that is used to clean drains, that can't be disposed of by putting it down the drain, well, OK, I guess.