1. In his authoritative speech as President of the British Association for the Advancement of Science, the physicist William Crookes (1832 - 1919) warns of the scarcity of resources, particularly nitrogen fertiliser.

  2. Robert Hasenclever (1841 - 1902), a soda producer in Stolberg, reports to the Aachen Scientific Society on desulphurisation of "smelting smoke", and publishes "On Harm to Vegetation Through Acid Gas" - a pioneering achievement in air quality.

  3. The zoologist Ernst Haeckel coins the term ecology to describe "the body of knowledge concerning the economy of nature - the investigation of the total relation of the animal both to its inorganic and to its organic environment"

  4. George Perkin Marsh (1801 - 1882) publishes his exhaustive "Man and Nature", reissued as "The Earth as modified by Human Action" in 1874. This is the first comprehensive description of the impact of human economic activity on land and sea around the world.

  5. Charles Darwin (1809 - 1882) finally publishes his landmark opus " On the Origin of Species by Means of Natural Selection...". The mechanics of nature and thereby the environment become more consciously understood.