Frank Lundquist developed the acid phosphatase test for semen witch helped determine if a victom was raped. Since acid phosphatase activity is 50 to 1000 times greater in semen than any other body fluid, finding a significantly high acid phosphatase level means that there is a presence of semen this is how frank lundquist discovered if the victom was raped or not. Lundquist took suspected semen samples and added drops of reagents and waited for a reaction. where there was seman the color would change to spotty and purple and if the sample was dark purple the amout of seman was higher. In the 1940s this test was a huge step for rape cases .