Stress-corrosion cracking of copper-base alloys is of considerable importance and has been the subject of many investigations which employed various accelerated tests and long-time service tests. The outstanding accelerated tests used are variations of either the mercury cracking test reported by Rogers in 1905(1) or the ammonia test reported in 1910(2). The ease of application of the mercury test is probably the reason industry adopted it. Subsequent investigation of this test(3,4) revealed that a minimum threshold stress was necessary before mercury cracking could develop.