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Webster 1913 Edition
Buhrstone
Buhr′stoneˊ
,Noun.
[OE.
bur
a whetstone for scythes.] (Min.)
A cellular, flinty rock, used for mill stones.
[Written also
burrstone
.] Webster 1828 Edition
Buhrstone
BUHR'STONE
,Noun.
This word is often written burr-stone.