Would someone explain this?

[bertoncini]

Correct...then it is vertical grain (quartersawn)

[Herman]

Since Honduran mahogany is very expensive, I buy the planks flatsawn. After cutting though the middle, I glue them "quatered" together. Good neckwood for half the price.
Herman

[Dave Bagwill]

Thinking, thinking........

[ken cierp]

Perhaps a different word or two --- ¼ sawn lumber is cut is such a way that the grain lines, when viewed from the end is running perpendicular to the width of the board – in other words it can be and is called vertical grain. Slab or flat sawn wood has the vertical grain lines perpendicular to the "narrow edge" of the board. So when you stack a sandwich of slabcut/flat sawn you in effect increase the width of the board (in this case the three combined narrow edges) which now can be defined as the width --- and sure enough the grain lines of the lamination are vertical – a fabricated ¼ sawn board/billet. Another thing to remember is that 1/4 sawn lumber is defined by a range of grain angle and in most cases the grain is not perfectly perpendicular.

[Dave Bagwill]

Okay, your combined efforts have allowed the dimmest bulb in my attic to light up. I get it now. Thanks!!

[bertoncini]

I think I saw the light come on from here :-)

[Dave Bagwill]

Dave, my sister in law in Tucson called to ask me what the bright light in the West was. I told her I figured out the quartersawn/flatsawn enigma and was met with a profound silence. My family is used to me, God bless 'em :-)