50 Years Ago

As pollution of crops and foodstuffs with pesticides increases, the continued use of persistent chemicals such as the chlorinated hydrocarbons, DDT and dieldrin, is being challenged. In the United States, Michigan and Arizona have already banned the use of DDT … while an organization known as the Environmental Defense Fund is fighting the continued use of the pesticides in a test case against the State of Wisconsin. From the beginning of 1970, DDT will also be banned in Sweden for domestic purposes … In Britain, the use of dieldrin and aldrin on spring sown seed has been banned since 1967, and a working party of the Advisory Committee on Pesticides and Other Toxic Chemicals is now reviewing the use of these pesticides in a wider context.

From Nature 17 May 1969

100 Years Ago

A memoir on Mars from the pen of Mr Harold Thomson, president of the British Astronomical Association, appears in Scientia for May. Mr Thomson narrates … the facts known about the planet from observation, and takes the very proper view that it is not specially the function of the astronomer to indulge in speculations as to the possibility of inhabitants of other worlds based on such facts, but only to collect them. Nevertheless, he makes the point that the changes in the form of the dark markings and in their positions may represent changes on the surface of the planet which have analogies on our Earth in the destruction of large forest areas, the ploughing up of vast tracts of land, or the changes caused by the operations of husbandry, and this may supply arguments to those who assert the existence of intelligent beings on Mars of as great weight as those furnished by the canals.

From Nature 15 May 1919