Justus Von Liebig - Research and Development

Research and Development

Liebig improved organic analysis with the Kaliapparat – a five-bulb device that used a potassium hydroxide solution to remove the organic combustion product carbon dioxide. He downplayed the role of humus in plant nutrition and discovered that plants feed on nitrogen compounds and carbon dioxide derived from the air, as well as on minerals in the soil. One of his most recognized and far-reaching accomplishments was the invention of nitrogen-based fertilizer. Liebig believed that nitrogen must be supplied to plant roots in the form of ammonia, and recognized the possibility of substituting chemical fertilizers for natural (animal dung, etc.) ones. Nitrogen fertilizers are now widely used throughout the world, and their production is a substantial segment of the chemical industry. He also formulated the Law of the Minimum, stating that a plant's development is limited by the one essential mineral that is in the relatively shortest supply, visualized as "Liebig's barrel". This concept is a qualitative version of the principles used to determine the application of fertilizer in modern agriculture.

He was also one of the first chemists to organize a laboratory as we know it today. His novel method of organic analysis made it possible for him to direct the analytical work of many graduate students. The vapor condensation device he popularized for his research is still known as a Liebig condenser, although it was in common use long before Liebig's research began. Liebig's students were from many of the German states as well as Britain and the United States, and they helped create an international reputation for their Doktorvater.

In 1835 he invented a process for silvering that greatly improved the utility of mirrors and in 1850 he investigated Spontaneous human combustion, dismissing the simplistic explanations based on ethanol due to alcoholism.

Liebig's work on applying chemistry to plant and animal physiology was especially influential. At a time when many chemists such as Jöns Jakob Berzelius insisted on a hard and fast separation between the organic and inorganic, Liebig argued that

...the production of all organic substances no longer belongs just to the organism. It must be viewed as not only probable but as certain that we shall produce them in our laboratories. Sugar, salicin, and morphine will be artificially produced."

Liebig's arguments against any chemical distinction between living (physiological) and dead chemical processes proved a great inspiration to several of his students and others who were interested in materialism. Though Liebig distanced himself from the direct political implications of materialism, he tacitly supported the work of Karl Vogt (1817–1895), Jacob Moleschott (1822–1893), and Ludwig Buechner (1824–1899).

Liebig played a more direct role in reforming politics in the German states through his promotion of science-based agriculture and the publication of John Stuart Mill's Logic. Through Liebig's close friendship with the Vieweg family publishing house, he arranged for his former student Jacob Schiel (1813–1889) to translate Mill's important work for German publication. Liebig liked Mill's Logic in part because it promoted science as a means to social and political progress, but also because Mill featured several examples of Liebig's research as an ideal for the scientific method. Liebig is also credited with the notion that "searing meat seals in the juices." This idea, still widely believed, is not true.

Working with Belgian engineer George Giebert, Liebig devised an efficient method of producing beef extract from carcasses. In 1865, they founded the Liebig Extract of Meat Company, marketing the extract as a cheap, nutritious alternative to real meat. Some years after Liebig's death, in 1899, the product was trademarked "Oxo".

Liebig is also credited with the invention of Marmite because of his discovery that yeast could be concentrated.

After World War II, the University of Giessen was officially renamed after him, "Justus-Liebig-Universität Giessen". In 1953 the West German post office issued a stamp in his honor.