Robbie,  Both Artecho and Art Echo are correct.  The roll labels are
marked in both formats.  I have never seen any rolls or literature
marked Art-Echo.

Has anyone copies of Art Echo or Apollo catalogs or bulletins later
than August 1926?  It would be marked Apollo at that late date.

Mark Reinhart
West Virginia
jimandmark@geocities.com

 [ We now have photo evidence of the spelling used by QRS, and at
 [ the Amphion shop.  But I don't know yet what Melville Clark called
 [ the system.   -- Robbie