CHAPTER IV. 

 TESTING OPERATIONS. TENSION TESTS. 



71. The tests which have most frequently to be made 

 in a testing machine are those in which the specimens 

 are subjected to a tensile load or pull. A tensile test 

 is easy to carry out, and the results are more readily 

 comparable than in the case of tests of other kinds. 

 Almost all the materials of construction may be readily 



FIG. 5.". 



subjected to tensile tests : these include the metals, ductile 

 and otherwise, timber, chains, hemp and wire ropes, and 

 cement; the exceptions are brick, stone, concrete, and 

 substances of like nature. 



