Wilhelm Rontgen was a German physicist and mechanical engineer. He is best remembered for producing and detecting X-rays for which he was honored with the first Nobel Prize in Physics in 1901. His discovery of X-rays remains one of the greatest achievements in the field of medical science.
Paul Hermann Müller was a Swiss chemist known for his discovery of insecticidal qualities and the use of DDT in the control of vector diseases. He received the 1948 Nobel Prize in Physiology or Medicine for this work. He began his career as a research chemist and later became the Deputy Director of Scientific Research on Substances for Plant Protection.
Bernard Courtois was a French chemist. He is credited with isolating iodine and morphine. Interested in chemistry from a young age, he learned how to make potassium nitrate for gunpowder for the French Revolution. He later found work at the École Polytechnique in Paris. Later in life, he went into manufacturing high-quality iodine and its salts.