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Less Is More It sounds all wrong--drilling holes in a piece of wood to make it more resistant to knocks.But it works because the energy from the blow gets distributed throughout the wood rather than focusing on one weak spot.The discovery should lead to more effective and lighter packaging materials. Carpenters have known ________centuries that some woods are tougher than others.Hickory，for example，was turned into axe handles and cartwheel spokesbecause it Can absorb shocks without breaking.White oak，for example，is much more easily damaged，_________ it is almost as dense.Julian Vincent at Bathe University and his team were convinced the woods internal structure could explain the differences. Many trees have tubularvessels that run _________ the trunk and carry water to the leaves.In oak they are large，and arranged in narrow bands，but in hickory they are smaller，and more evenly distributed.The researchers _________ this layout might distribute a blows energy throughout the wood.soaking up a bigger hit.To test the idea，they drilled holes 0.65 millimetres across into a block of spruce，a wood with _________ vessels，and found that _________ withstood a harder knock._________ when there were more than about 30 holes per square centimetre did the woods performance drop off. A uniform substance doesnt cope well with knocks because only a small proportion of the material is actually _________ .All the energy from the blow goes towards breaking the material in one or two places，but often the pieces left _________ are pristine. | 
