John,
As Tom Holloway has indicated, this is a desirable and uncommon plane. The
1867 & 1869 patented planes with the swinging lever cap are the first
models made by the Auburn Metallic Plane Co., which continued in business
until 1878. A good deal of the history and products of the company are in
Roger Smith's PTAMPIA ("Patented Transitional and Metallic Planes in America,
1827-1927"), Volume 1, which is a must have for anyone interested in the
subject. The company was very successful, and seems to have sent a fair
amount of their product to the midwest where the planes turn up, it appears
to me, with disproportionate frequency compared to, say, New England. I
also believe that the success of the designs, quality and sales of Auburn
Metallics in the 1870s was directly responsible for Stanley adding (in
1876) the Liberty Bell line of "Stanley" planes and the 110 series of block
planes to offer a cheaper alternative to the Bailey bench and 9 1/2 blocks.
A careful comparison-review of price lists of Auburn Metallic and Stanley for
the years of 1869-1878 shows that Auburn *invariably* undercut the Baileys in
the price of each model- bench plane, transitional & block. The Liberty Bells
and 110 series of Stanley planes, however, were less expensive than the Auburn
product.

Your plane does have a movable throat.  Loosen up the front knob- if
necessary soak the threads at the base of the front knob with some
penetrating oil and give it a determined twist to unscrew the knob. Tap out
the throat adjusting plate from above using the exposed & tapped socket,
and a little cleaning will loosen it up to move smoothly.

I can't just now think of who the maker of your iron is. Original Auburn
Metallics had Excelsior, Metallic Plane Co., Auburn, N.Y.  I'll keep
staring at the letters for a while longer.

Nice find! Reassure SWMBO that you have been stewarding the family treasury
intelligently. :-)

Regards,

Dan
-Dan Weinstock
Geneva, N.Y.

weindan@h...