Theodor Schwann

Theodor Schwann portrait
Theodor Schwann

Theodor Schwann (1810 – 1882) was a German physician and physiologist who proposed the cellular nature of all living things.  Along with Matthias Schleiden, Schwann laid down the foundation to Cell Theory.

Schwann was born in Neuss, Germany, attended a Jesuit school in Cologne, enrolled in the University of Bonn, transferred the the University of Wurzburg for clinical training in medicine before he finally moved the the University of Berlin where he obtained his M.D. degree.  Much of his moving involved him following physiologist Johannes Muller, a leading physiologist of his time.

After he graduated he began to make a series of discoveries.  In 1835 he discovered the enzyme Pepsin.  Next he performed experiments with yeast and fermentation.  He successfully demonstrated that fermentation was an organic process; that living yeast was necessary to produce more yeast.

Schwann’s most important work was in the development of Cell Theory.  He began by taking the idea that all plants are made from cells and extended them to animals.  In 1838 Schleiden published Contributions to our Knowledge of Phytogenesis, outlining his theories of the roles of cells in plant development.  This influenced Schwann and the next year he published Microscopical Researches into the Accordance in the Structure and Growth of Animals and Plants, a landmark work where he proposed his own Cell Theory.  In it he exclaimed ” “All living things are composed of cells and cell products”, extending Schleiden’s idea that new plant cells are formed from old plant cells to the domain of animals.   He also coined the term “metabolism” to describe chemical reactions taking place within the cell.

Cell Theory and his work on yeast and fermentation provided strong evidence against the idea of spontaneous generation – the idea that living organisms could develop from nonliving matter.  This won him tremendous respect from his peers.  In 1879 Schwann was elected to both the Royal Society and to the French Academy of Science.  He died three years later.

Matthew Maury

Matthew Maury portrait
Matthew Maury

Matthew Maury (1806 – 1873) was an American Naval officer and oceanographer.  He is credited with the moniker “Father of Modern Oceanography” thanks to the comprehensive book on oceanography he published in 1855, The Physical Geography of the Sea.

Maury was born into a Huguenot family in Virginia but had moved to Tennessee by the time he turned five.  His brother John was a Navy officer and Matthew was determined to follow suit.  He obtained a naval appointment at age 19 from Tennessee Representative Sam Houston.  He immediately began studying the sea on a four-year voyage aboard the Vincennes that began in 1826.  It was the first US Naval warship to circumnavigate the globe.  Sadly, his seafaring days came to an abrupt end at the age of 33 after his leg was maimed in a stagecoach accident.  Henceforth he would devote his time to studying the ocean.

In 1842 Maury was placed as head of the Depot of Charts and Instruments in Washington DC, which offered him a tremendous amount of maritime data in terms of log books and various other records.  He would eventually turn this institution into the United States Naval Observatory and become its first superintendent.

In 1855 he published the first modern oceanography textbook, The Physical Geography of the Sea, describing the winds, currents, climate, and physical geography over the worlds oceans.  That same year Maury proposed sea lanes in his book Sailing Directions.  This idea was taken up by the major shipping companies to the benefit of lives and dollars saved.  He also sent out survey ships to take depth readings on the Atlantic Ocean’s floor, which revealed the Mid-Atlantic ridge.  His books and his surveys helped to prove the feasibility of laying a first transatlantic cable, which occurred in July 1866.

The American Civil War interrupted his career, sending him to Europe and then to Mexico before he finally returned to Virginia where he took the post of professor of meteorology at the Virginia Military Institute.  He stayed there until his death in 1873.