Thanks to all of the Galoots who responded. My $1 flea market purchase has just
sat on a table staring at me.  In 1959 or 1960 my father bought a house that had
been that had been built in the 1850's.  I was just a wee tyke but I remember
the fluidness of the carpenters using their "zig-zag" folding rulers.  In the
1970's when I was framing houses I never saw a folding ruler on a job site.
Never. I think that I will clean this Lufkin No. X45 (or maybe it's X46?) with
some Murphy Oil Soap for the wood and use a brass tooth brush for the metal
joints.  Then add a drop of 3-in-1 oil to each joint and work the joint back and
forth.  Unless someone has a better method of cleaningthis tool?  Then I'll
probably stick it in the back of a tool box with my other smaller folding
woodenrules and forget about it for the rest of my life.   I use a tape measure
for the big stuff.  I reach for a 25' most of the time just for the extension of
the blade.  For more precise stuff I use 6"  (I bet I have a dozen or more of
them), 9", 12" (I bet I score adozen of these too), 16", 18", or 1 meter rules.
But my favorite measuring devise is a story stick. Thanks again. chuck P.S. I'd
love to see a video of the magic way of opening a 6' folding rule.
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