Science Events By Mlloyd13 Sep 4, 1895 X-rays were discovered Jun 3, 1912 X-ray Diffraction Nov 3, 1932 Discovery of nuetron Aug 3, 1943 DNA Oswalk Avery proves that DNA is genetic material of chromosome Nov 1, 1952 Jonas Salk: developed and tested first polio vaccine Nov 1, 1997 Dolly the sheep was cloned
