Ladder

Claim 1

A ROLL-UP LADDER COMPRISING A PAIR OF RAILS; EACH RAIL COMPRISING A PLURALITY OF HOLLOW BLOCKS HELD SUBSTANTIALLY IN CONTACT WITH EACH OTHER, EACH OF SAID BLOCKS BEING L-SHAPED IN CROSS SECTION AND HAVING A RELATIVELY NARROW HOLLOW SUBSTANTIALLY HORIZONTAL PORTION AND A LONGER SUBSTANTIALLY VERTICAL HOLLOW PORTION, THE SUBSTANTIALLY HORIZONTAL SECTION BEING SUBSTANTIALLY AT RIGHT ANGLES TO THE SUBSTANTIALLY VERTICAL SECTION; MEANS IN THE HOLLOW BLOCKS FOR HOLDING THE BLOCK TOGETHER IN SUBSTANTIAL CONTACT; AND A SEPARATE TENSION MEMBER POSITIONED WITHIN THE SUBSTANTIALLY VERTICAL PORTION OF THE HOLLOW BLOCKS COMPRISING MEANS FOR HOLDING THE LADDER EXTENDED IN COMBINATION WITH MEANS, COMPRISING A PLURALITY OF ARCHED MEMBERS POSITIONED IN THE SUBSTANTIALLY VERTICAL PORTION OF THE L-SHAPED HOLLOW, FOR AUTOMATICALLY MOVING THE TENSION MEMBER TO THE EXTREME END OF THE SUBSTANTIALLY VERTICAL PORTION OF THE L-SHAPED HOLLOW OF EACH OF THE BLOCKS OPPOSITE TO THE SUBSTANTIALLY HORIZONTAL PORTION OF THE BLOCKS, EACH SUCH ARCHED MEMBER HAVING AT LEAST A PORTION THEREOF POSITIONED WITHIN THE HOLLOWS OF A PLURALITY OF SAID HOLLOW BLOCKS.