Brigham

Period Stamp

Three dots on the stem, arranged horizontally, vertically, or in a triangle, sometimes as one large dot with two small ones.

—	[Three dots, horizontal]
—	[one large dot, two small dots]
—	[Three dots, vertical]
—	[Three dots, in a triangular arrangement]
Underside	388 2, Brigham, Canada

Three dots set side by side on the stem correspond to the 600 series shape numbers, while three dots in a triangle correspond to the 300 series.