A shorter course in woodworking; a practical manual for home and school . ^ ^ ^ ^ ^^ J^m race Fig- 551 u u u u u u Fig. 552 Lay a twig across two supports, hang a weight at the middle and seewhat happens (Fig. 553). The bark will pucker on the upper side of thetwig, showing that the top is being shortened or compressed. The barkwill be stretched and perhaps cracked apart on the under side, showingthat the lower part is being lengthened or pulled out (or subjected to tension)^Now, if you lay a piece of timber 2 x 8 across a brook for a bridge, or as a m—^Compression « w B.

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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyorklondongpput