: That's a little bit of a different beast. That is called a
: "sacrificial anode" and as the name suggests, it is
: designed to sacrifice itself instead of the metal, but it is
: sacrificing against electrolysis, which is enhanced by salt
: water. It isn't so much stopping rust, but rather corrosion by
: electrolysis, called galvanic corrosion. It wouldn't have any
: effect with stopping rust topsides.

: There are actually formulas to figure out just the right anode for
: your particular vessel so that you have just the right amount of
: zinc to offset the metals underwater. The most amazing thing I
: have seen are these little rings that you can buy for setting
: fish pots and lobster pots. You tie a buoy to the ring, throw
: the pot in the water, and the pot drags the buoy down with it.
: The rings are made of zinc and are designed to corrode in salt
: water at a specific rate. You buy them for 24, 48, 72 hours. My
: friend had put a string out and I went out to help him bring
: them in. He used a GPS to mark them so he knew exactly where
: they were. We got there exactly 24 hours after he put them
: under. We sat there and he said, "They're here, they should
: be popping up pretty soon." Well lo and behold, right then
: they all started to pop up at exactly the same intervals at
: which we had thrown them in, exactly 24 hours from the time we
: did it, and all just by a little zinc ring that is designed to
: corrode within a specific amount of time. Amazing stuff.

: Back to rust stopping, they do sell a thing that you can put in
: your tool drawer that emits a layer of gas of some sort due to
: some sort of chemical reaction, and that layer blankets the
: tools and keeps moisture out. Supposedly it works, but of course
: it depends on a good tight seal on the drawers. A couple of
: months ago Fine Woodworking did a test of rust preventative
: measures. You can look it up there.
3 months ago a coworker gave me a old 30 piece set that his father used when he was younger(passed away many years ago). All shapes and sizes with stones. On the blades it says -MERRINGBROS,London. Sofare I have only used them to shape the internal stems after the outside was glassed.