Barcol hardness test
... that the Barcol hardness test was developed during World War II for the U.S. Army Air Corps to check that airplane rivets had not been sabotaged?
... that the <b id="mwDO8"><a href="./Barcol_hardness_test" id="mwDPA" rel="mw:WikiLink" title="Barcol hardness test">Barcol hardness test</a></b> was developed during <a href="./World_War_II" id="mwDPE" rel="mw:WikiLink" title="World War II">World War II</a> for the <a href="./United_States_Army_Air_Corps" id="mwDPI" rel="mw:WikiLink" title="United States Army Air Corps">U.S. Army Air Corps</a> to check that airplane <a href="./Rivet" id="mwDPM" rel="mw:WikiLink" title="Rivet">rivets</a> had not been sabotaged?