Aaron, I've rebuilt several Mason & Risch pianos, and the safest way to find the date of manufacture is the stamp on the action. Look closely, does it have a month and day next to the 1910? That should be your year. Mason & Risch serial numbers are notoriously incorrect in the Pierce Atlas, I find Canadian sources are better, such as the Canadian Piano Atlas, formerly from D.M. Best, now from Pianophile. Also, is this a Mason & Risch stencil piano, such as Harmonic, Haddon Hall, etc? The numbers will be different again for some of these names (Harmonic, for sure). I'll see what my atlas says when I get to work today, =E0 bient=F4t, Rob Kiddell R.P.T., P.T.G. C.A.P.T. Student Edmonton, Canada http://www.planet.eon.net/~atonal/atonal.html
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