Concave/Convex Bamboo

[xbmedic]

Ok. Now that I have built several glass laminated Hill style bows, I wanted to try my hand at one like Howard Hill made in the 1930's of laminated bamboo without glass. I found a patent that Howard Hill received in 1941 for a concave/convex bamboo bow stave here:
  http://www.google.com/patents/US2256946  
I have several pieces of tonkin cane that I have shaped like the drawing, removing the inner nodes and some of the pith. I have not tempered or tapered the laminations yet. I also have not knocked down the outer nodes or taken any of the rind off of the outside of the bamboo yet. I have done an exhaustive search of both Tradgang and the rest of the web to find out more information about tempering, tapering, and assembly of this type of stave without results. Can anybody help me?

[Tom Leemans]

hmmmm...where have I seen that cross section before?