July 27

Born in Basel in 1667, Johann Bernoulli was the younger brother of Jakob Bernoulli and became a leading figure in the early development of calculus. He held professorships at the University of Groningen and later at the University of Basel. His contributions include work on infinite series, exponential functions, and the formulation of Bernoulli's differential equation. Bernoulli's rivalry and collaboration with his brother and students shaped the mathematical landscape of the 18th century. He died in 1748, leaving a lasting Bernoulli legacy.

Born in 1733 in England, Jeremiah Dixon trained in astronomy and surveying before embarking on the famous Mason–Dixon survey in 1763. Working alongside Charles Mason, he used astronomical observations to determine latitude and established the boundary between Pennsylvania and Maryland. Dixon later continued work for the British East India Company in Sumatra. His precise measurements and methods set new standards in geodesy. He died in 1779, leaving behind one of the most enduring lines in American colonial history.

Born in 1773 at the Nes Iron Works, Jacob Aall was educated in Germany and returned to manage his family's industrial enterprises. He wrote influential works on Norwegian history and politics, advocating for constitutional governance. Aall represented Schleswig at the Norwegian Constituent Assembly in 1814, helping draft the nation's constitution. He served in the Norwegian Parliament, promoting economic development and educational reforms. His dual contributions to industry and political thought left a lasting legacy in Norway's path to independence.

Born in Glasgow in 1777, Campbell studied at the University of Glasgow and later at Trinity College, Cambridge. His first major success came with the 1799 publication of 'The Pleasures of Hope', a poem celebrated across Europe. Campbell's rich imagery and patriotic themes resonated during a time of revolutionary change. He traveled widely on the continent, producing works that blended classical influences with Romantic sentiment. Appointed regius professor of history at the University of Glasgow late in life, he continued to write and inspire future poets.

Born in 1833, Thomas George Bonney studied geology at University College London before embarking on an academic career. He served as Professor of Geology and was elected President of the Geological Society of London, where he promoted rigorous fieldwork and research. An avid mountaineer, Bonney made numerous first ascents in the Alps and Scottish Highlands, often combining exploration with geological observation. He published influential textbooks and papers on igneous rocks, volcanic activity, and mountain geology, shaping the discipline for future generations. Bonney's dedication to both scientific inquiry and education left a lasting mark on geology. He continued his work until his death in 1923.

Born in 1848 into a noble Hungarian family, Loránd Eötvös earned his doctorate in physics and studied under Lord Kelvin in Britain. He later became a professor at the University of Budapest, where he developed the torsion balance experiment to measure differences in gravitational acceleration with unprecedented precision. His work confirmed key aspects of the equivalence principle and laid the groundwork for modern geophysics. In 1901, Eötvös was appointed Minister of Education of Hungary, promoting scientific research and educational reform. He also presided over the Hungarian Academy of Sciences, fostering international collaboration. Eötvös died in 1919, leaving a profound impact on both science and public service.

Born in 1848, Friedrich Ernst Dorn studied at the University of Strasbourg and later served as a professor at the University of Wrocław. He investigated the decay products of radium and observed an unknown radioactive emanation, later identified as radon. Dorn's careful experimental work contributed to the early understanding of radioactive elements and their properties. He published numerous papers detailing the behavior of radon and its occurrence in minerals. Dorn was also respected as a teacher, mentoring students in the emerging field of nuclear physics. He remained active in research until his death in 1916, and his discovery of radon paved the way for advances in atomic science.

Ernest A. Wallis Budge (1857–1934) was a pioneering English Egyptologist and philologist. He joined the British Museum in 1883 and became Keeper of Egyptian and Assyrian Antiquities in 1894, a post he held for thirty years. Budge published numerous translations of ancient texts, including his influential rendition of the 'Egyptian Book of the Dead.' His scholarship helped popularize the study of ancient Near Eastern languages and cultures among both academics and the general public. Despite later criticism of his methodology, his extensive cataloguing and publications laid important foundations for modern Egyptology.

Hans Fischer (1881–1945) was a German organic chemist and professor known for his groundbreaking work on porphyrins. He conducted research that clarified the chemical structure of hemin, the pigment in red blood cells, and later elucidated the molecular structure of chlorophyll. Fischer held academic positions at the University of Leipzig and the Technical University of Munich, where he also served as rector. In 1930, he was awarded the Nobel Prize in Chemistry for his contributions to the understanding of biological pigments. His work laid the foundations for modern studies in bioorganic chemistry and physiology.

Geoffrey de Havilland was born in 1882 in London and developed a passion for flight from a young age. He flew as a pilot for the Royal Aircraft Factory during World War I and contributed to early military aircraft designs. In 1920, he established the de Havilland Aircraft Company, creating landmark aircraft like the DH.4 bomber and the Mosquito. His innovative work in lightweight wooden aircraft structures revolutionized performance and manufacturing techniques. Knighted in 1944, he oversaw the growth of his company into a leading global aerospace manufacturer. De Havilland's designs influenced generations of engineers and remain celebrated in aviation history.

Benjamin Miessner was born in 1890 and pursued electrical engineering at the University of Wisconsin. He developed key components for radio transmitters and receivers, improving signal clarity and range. Miessner held over 150 patents related to communication technology and sound reproduction. In the 1920s and 1930s, his work influenced the growth of commercial radio and public broadcasting. Later in his career, he focused on high-fidelity audio systems and contributed to early television research. His inventions laid groundwork for modern communications and entertainment electronics.

Jacob van der Hoeden was born in 1891 in the Netherlands and specialized in veterinary medicine. He emigrated to Mandatory Palestine in the 1920s, where he founded the veterinary institute in Rehovot. As a professor at the Hebrew University, he conducted vital research on zoonotic diseases. His work improved animal health standards and contributed to public health in the region. Van der Hoeden trained generations of veterinarians and established laboratory facilities for scientific study. He is remembered as a foundational figure in Israeli veterinary science.