Gerhard Henrik Armauer Hansen (1841-1912)

He was well known for his pioneer study of leprosy - a prominent disease in the history of human sufferings.

Armauer Hansen was the discoverer of the causative agent of leprosy. Armauer Hansen was born in 29 July 1841 in Bergen, Norway. He entered the University of Christiana to study medicine in 1859. He obtained his degree in medicine in 1866, and completed his internship at the National Hospital in Christiania. After about two years at Bergen’s Leprosy Hospital he underwent a period of study in Vienna, where he became familiar with the ‘germ theory’ of disease.

Returning to Bergen, Hansen was by now convinced that leprosy was a specific communicable disease. In 1873, he discovered rod-shaped bodies later identified as M. leprae. He published his observations in 1874. By improving his staining technique in 1879, he was able to show great numbers of rod-shaped bacteria typically aggregated in parallel.

In 1880 Hansen named the organism causing leprosy as Bacillus leprae. When Lehman and Neumann erected the new genus Mycobacterium in 1896, it was transferred to this genus and henceforth ahs be known as Mycobacterium leprae.

He believed that the bacillus was the etiological agent of leprosy, which proved to be true. Hansen’s publication from 1874, Preliminary Contributions to the Characteristics of Leprosy, is the earliest description of a microorganism as the cause of a chronic disease.
Gerhard Henrik Armauer Hansen (1841-1912)

Jagadish Chandra Bose

Jagadish Chandra Bose was born in the 30th of November 1858 in Faridpur in Dacca District. His father Bhagaban Chandra Bose was a Deputy Magistrate.

Jagadish Chandra Bose had his early education in village school in Bengla medium.  In 1869, Jagadish Chandra Bose was sent to Calcutta to learn English and was educated at St. Xavier’s School and College. He graduated with degree in science from St. Xavier’s College Calcutta in 1879.

In London he first studied medicine. But he repeatedly fell ill. So he had to discontinue the course. In 1880, he received admission and studied Natural Science in Christ Church College, Cambridge.

At Cambridge, he worked with a professor of physics, Lord Rayleigh. It was here that he befriended with the famous biologist Dr Sidney Vines and became interested in biology.

Returned from Cambridge in 1885, he was appointed a Professor of Physics in Presidency College, Calcutta. Here, he initiated his experiments in various areas in physics and botany.

He invented wireless telegraphy in 1895 a year before Guglielmo Marconi patented his invention.

He converted a small enclosure adjoining a bathroom in the Presidency College into a laboratory. He carried out experiments involving refraction, diffraction and polarization.

Chandra Bose received the D.Sc degree of London University in 1896 for his work on the determination of wavelength of electric radiation by diffraction grating.

In 1915, he left the university to found the Bose Research Institute, Calcutta.  He was able to interest the world’s scientists in his work and his fame grew. Jagadish Chandra Bose died on November 23, 1937.
Jagadish Chandra Bose

Martinus Willem Beijerinck (16 March 1851 – 1 January 1931)

Martinus Willem Beijerinck was born in Amsterdam and came from a wealthy family in which his father had failed to maintain the tradition of success.

He received his secondary education at the HBS in Haarlem and from 1868 to 1872 studied chemical technology at the Delft Polytechnic School.

While he was a teacher in various schools Beijerinck studied botany at Leiden from 1872 onwards.

In 1876 he got a job as a botany lecturer at the Higher School of Agriculture, Horticulture and Forestry in Wageningen.

Here he also had time to work on his research into plant galls, with which he gained his doctorate cum laude in 1877.

Beijerinck worked for the Netherlands Yeast and Alcohol Factory in Delft from 1887 to 1893, before returned to the Delft Polytechnic School, where he founded a new microbiology laboratory in 1897.

Beijerinck spent most of his life studying microorganisms in the soil and in crop plants. In the 1890s, several European researchers were studying a disease of tobacco plants known as tobacco mosaics disease because it cause the leaves to become mottled with light and dark spots.

In 1898 Beijerinck discovered the agent that causes the disease can pass through a laboratory filter. Since such filters retain bacteria and other known microorganisms, Beijerinck believes that the agent is a new type of organism.

Beijerinck called the mystery agent a virus, the Latin world for poison. He published his conclusion about tobacco mosaic virus in 1898.
Martinus Willem Beijerinck (16 March 1851 – 1 January 1931)

Michel-Eugene Chevreul (1786-1889)

Chevreul studied at the College de France in 1803. He was an assistant to Antoine Francois de Fourcroy in 1809 and assistant to the Musee d’Hisotrie Naturalle.

In 1813 he then became professor of physics at the Lycee Charlemagne. Fats are used in manufacturing soap and as a young man Chevreul was involved in that business. He discovered the first fatty acid whole studying potassium soap made from pig fat.

He was able to isolate different insoluble organics acids - also called carbonic acids, or fatty acids. He named several fatty acids, including oleic, butyric, caproic and capric acids and stearic acid.

Chevreul also demonstrated that all fatty acids are composed of a carboxylic acid (-COOH) with a long carbon tail (4-24 carbon atoms in length).

His discovery of extract stearic acid from animal fat in 1823, led to the development of stearin wax. Candles made from stearin wax were harder and burned longer and cleaner than unrefined tallow candles.

He also discovered hematoxylin, which became an important stain for tissue microscopy, and investigated how a color image could be formed from large numbers of small spots each of a single color (currently call pixels).
Michel-Eugene Chevreul (1786-1889)

William Harvey (1578-1657) and blood circulation

William Harvey was an English doctor who closely observed the bodies of his patients and of animals. He realized that blood flowed round the body. He saw in the action of the heart in small animals and fish what was going on in people.

William Harvey was born in Folkestone, a small fishing village on the English Channel not far from Dover on the first day of April in 1578.

He was a student of medicine in 1600 and mastered the traditional theory of human physiology as well as all the scientific theory and medical practice that depended on it and supported it.

Harvey’s admission to the fellowship of the Royal College of Physician (1607), his appointment as Physician to St Bartholomew’s Hospital (1609), as Lumleian Lecturer in Anatomy (1615) and as Physician Extraordinary to the King are the great landmarks of the Jacobean period in Harvey’s life.

In 1628, Harvey published his revolutionary ‘circulation’ theory of the movement of the blood. He was the first doctor to actually describe the circulation in the body accurately.

Harvey’s discovery, which controverted the ancient theory of Galen, is one of the vital, incontestable breakthroughs in the history of science and medicine.
William Harvey (1578-1657) and blood circulation

Friedlieb Ferdinand Runge (1794-1867)

He was a German pharmacist who discovered aniline, which he called ‘kvanol’, in a coal tar in 1834. 

Friedlieb Ferdinand Runge was born in Billwarder, near Hamburg, 8 February 1795. Runge studied pharmacy before leaving his hometown in 1816 for Berlin, Jena and Gottingen to study medicine.

Runge obtaining a doctorate in philosophy in 1822 for De pigmento Indico eiusque conubiis cum metallorum nonnulorum oxydis.

He began his career as a pharmacist and after a long residence in Paris, became an associate professor of technological chemistry at the University of Breslau, Germany.

Later he served in the Prussian Marine in Berlin and Oranienburg. In 1834 he discovered carbolic acid, rosolic acid and other chemicals in the same substance. This was the beginning of coal-tar chemistry.

In 1820 he isolated an alkaloid from the coffee bean, which he dubbed ‘caffeine’ indicating something found in coffee.
Friedlieb Ferdinand Runge (1794-1867)

Dr Emil Christian Hansen (1842-1909)

Emil Christian Hansen came from a modest family. Originally trained as a house painter and a primary school teacher, Hansen later became a botanist and a mycologist. Hansen is said to have written novels and sold them: Form this income he financed his studies.

Emil Christian Hansen in 1876 was awarded a gold medal by the University of Copenhagen for his study of the coprophilous fungi of Denmark and three years later gained a PhD for a thesis on yeasts.

In 1877, he was employed as a fermentation physiologist as the Carlsberg Brewery. In 1883, Hansen succeeded in producing bottom-fermented beer on a large scale for the first time, using ‘the sop-called pure culture yeast’.

Hansen used a dilution method to isolate pure cultures of brewing yeast, derived from a mixed culture that occasionally produced poor quality beer.

This made it possible to prevent beer form being spoiled by the action of wild yeasts in the vat. In the same year, for the first time in history, the Carlsberg Brewery started industrial production of lager beer with one of the Hansen’s pure culture.
Dr Emil Christian Hansen (1842-1909)