XVI] THE STRUCTURE OF BONE 679 



Schwendener* shewed that the strength was concentrated in the 

 Httle bundles of "bast-tissue," but that these bast-fibres had a 

 tensile strength per square mm. of section, up to the hmit of 

 elasticity, not less than that of steel-wire of such quality as was 

 in use in his day. 



For instance, we see in the following table the load which 

 various fibres, and various wires, were found capable of sustaining, 

 not up to the breaking-point, but up to the "elastic Hmit," or 

 point beyond which complete recovery to the original length took 

 place no longer after release of the load. 



In other respects, it is true, the plant-fibres were inferior to 

 the wires ; for the former broke asunder very soon after the 

 limit of elasticity was passed, while the iron-wire could stand, 

 before snapping, three times the load which was measured by its 

 limit of elasticity: in the language of a modern engineer, the 

 bast-fibres had a low " peld-point," httle above the elastic limit. 

 But nevertheless, within certain limits, plant-fibre and wire were 

 just as good and strong one as the other. And then Schwendener 

 proceeds to shew, in many beautiful diagrams, the various ways 

 in which these strands of strong tensile tissue are arranged in 

 various cases : sometimes, in the simpler cases, forming numerous 

 small bundles arranged in a peripheral ring, not quite at the 

 periphery, for a certain amount of space has to be left for living 

 and active tissue; sometimes in a sparser ring of larger and 



* Das mechanische Prinzip im anatomischen Bau der Monocotylen, Leipzig, 

 1874. 



