February 15

Galileo Galilei made groundbreaking observations with early telescopes, including Jupiter's moons and lunar craters. He conducted experiments on motion, formulating principles that prefigured Newton's laws. His advocacy of the heliocentric model brought him into conflict with the Catholic Church and the Inquisition. Galileo improved scientific instruments and wrote influential works such as 'Sidereus Nuncius' and 'Dialogue Concerning the Two Chief World Systems'. His methods established the importance of experimentation and mathematical analysis in science. He spent his later years under house arrest but continued to write and refine his scientific ideas.

Born in the Principality of Brunswick-Wolfenbüttel, Wolf studied theology and classical languages at Helmstedt and Göttingen. In his seminal work “Prolegomena ad Homerum,” he applied rigorous textual criticism to ancient Greek epics. Wolf challenged traditional authorship views, proposing the Homeric Question about the composition of the Iliad and Odyssey. As a professor at Halle, he established philology as an academic discipline and trained future scholars. His methodological innovations transformed the study of classical texts and influenced 19th-century humanistic scholarship. Wolf’s legacy endures in the critical techniques used in literature and historical source analysis.

Born in Tongeren, André Dumont studied geology and mineralogy at the University of Liège. He conducted extensive surveys of Belgium’s geology, mapping coal deposits critical for the Industrial Revolution. Dumont’s work on stratigraphy and paleontology advanced understanding of geological layers and fossil records. He served as a professor at the University of Liège, training future geologists and engineers. His publications, including a geological map of Belgium, became fundamental references for researchers and industry. Dumont’s legacy endures in modern geological sciences and resource exploration methods.

V. A. Urechia was born in 1834 in the Moldavian principality and became a leading historian and literary figure. He authored influential studies on the cultural and political evolution of the Romanian principalities. As a playwright, Urechia crafted dramas that explored national identity and social issues of his time. He contributed essays and criticism to literary journals, advocating for educational reform and cultural development. Urechia founded and directed academic institutions, promoting modern scholarship in Romania. His writings blended rigorous research with patriotic vision, helping to shape Romanian national consciousness. He died in 1901, remembered for his dual legacy as a scholar and man of letters.

Sir Rickman Godlee was born in 1849 in London and became a pioneering English surgeon. He performed the world's first recorded complete removal of a brain tumor in 1884, advancing neurosurgical techniques. Godlee held academic positions at University College Hospital and served as President of the Royal College of Surgeons. He published extensively on surgical methods and medical education, shaping modern surgical practice. He passed away in 1925, remembered for his innovative contributions to brain surgery and medical training.

Sophie Bryant was born in Ireland in 1850 and became one of the first women to earn a doctorate in mathematics. She excelled academically at Girton College, Cambridge, and later led North London Collegiate School as headmistress. Bryant published work on geometric theory and advocated for women's rights and educational reform. She was a founding member of several suffrage organizations and served as President of the Mathematical Association. She died in 1922, leaving a legacy as both a scholar and an activist.

Spiru Haret was born in 1851 in Romania and studied mathematics and astronomy in Paris. He made significant contributions to celestial mechanics, particularly on the n-body problem and lunar motion. Haret served as Minister of Public Instruction and Interior, where he reformed the education system, expanded access to schools, and modernized curricula. His policies led to increased literacy and the establishment of numerous high schools across Romania. Haret's work bridged science and politics until his death in 1912.

Emil Kraepelin was born in 1856 in Neustrelitz, Germany, and became a founding figure in modern psychiatry. He differentiated between manic-depressive illness and dementia praecox, laying the groundwork for contemporary diagnostic categories. Kraepelin authored the influential textbook 'Psychiatrie', which guided psychiatric education for decades. He held professorships in Dorpat and Munich, advancing research into the biological basis of mental disorders. He died in 1926, leaving a profound impact on psychiatric classification and practice.

Charles Édouard Guillaume was born in 1861 in Fleurier, Switzerland, and became a leading physicist at the International Bureau of Weights and Measures. He discovered Invar and Elinvar alloys, which revolutionized precision instruments by minimizing expansion and elasticity changes. His work on metrology and standards earned him the Nobel Prize in Physics in 1920. Guillaume served as director of the Bureau and published extensively on measurement science. He died in 1938, having shaped modern standards for scientific accuracy.

Hans von Euler-Chelpin was born in 1873 in Augsburg, Germany, and became a distinguished biochemist in Sweden. He elucidated the enzymatic mechanisms of fermentation, sharing the Nobel Prize in Chemistry in 1929. Euler-Chelpin served as a professor at the University of Stockholm and wrote extensively on enzymology. His research advanced the understanding of biochemical processes and paved the way for modern biochemistry. He died in 1964, remembered as a pioneer in the study of enzymes.

Norman C. Deno (1921–2017) was an American chemist and plant scientist whose groundbreaking studies transformed seed physiology and germination techniques. After earning his Ph.D. in chemistry, he joined the University of Minnesota and developed methods to improve germination rates across diverse plant species. Deno authored the seminal book Seed Germination Theory and Practice, a key reference for horticulturists and botanists. His work advanced agriculture, conservation, and public interest in plant sciences.

Angella D. Ferguson is an American pediatrician and researcher who specialized in childhood lead poisoning. She graduated from the University of Michigan Medical School and began her career at Freedmen's Hospital in Washington, D.C. Ferguson's groundbreaking studies in the 1970s established the harmful effects of low-level lead exposure in children. Her work contributed to policy changes and public health initiatives to reduce lead contamination. She has been recognized for her advocacy in pediatric health and environmental safety.