51����

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ACROSS

�������� 9���� Chemical compound widely used as an insecticide (15)

���� 10���� Name given to certain species of baleen whale (7)

���� 12���� Thomas ___ (1757–1834), Scottish engineer, best-known for the Menai Bridge in Wales (7)

���� 13���� References to other work (in scientific papers and so on) (9)

���� 14���� A group of apes, baboons or lemurs (5)

���� 15���� Old term for a painkilling drug (7)

���� 18���� The ___, 1623 work by Galileo Galilei (7)

���� 21���� Paul ___ (1902–84), British theoretical physicist (5)

���� 23���� In a fraction, the integer placed above the line (9)

���� 25���� A completed loop, in electronics (7)

���� 26���� In geometry, lozenge- or diamond-shaped (7)

���� 29���� Program that manages a computer’s software and hardware (9,6)

DOWN

�������� 1���� Niels ___ (1885–1962), Danish physicist (4)

�������� 2���� Jelly-like substance often used in microbiological experiments (4)

�������� 3���� California city, noted for its many manufacturing businesses and small population (8)

�������� 4���� US human spaceflight programme launched in 1961 (6)

�������� 5���� Ocean region beneath which the Viking Gas Field was discovered in 1965 (5,3)

�������� 6���� In computing, a small application – often a plug-in – that performs a specific task (6)

�������� 7���� The science of classification (8)

�������� 8���� Aluminosilicate mineral that makes up more than half of Earth’s crust (8)

���� 11���� Constellation in which the stars Betelgeuse and Rigel can be seen (5)

���� 15���� In the human body, a muscle that draws towards the centre of the body or limb (8)

���� 16���� Mechanical models of the solar system (8)

���� 17���� ‘___ was a giant. His head was in the clouds, but his feet were on the ground’ – Richard Feynman (8)

���� 19���� Red-striped form of the mineral chalcedony (8)

���� 20���� Bacterium that can cause severe food poisoning in humans (1,4)

���� 22���� Concerned with actions and their consequences (6)

���� 24���� An optical illusion – or a French combat aeroplane (6)

���� 27���� Second letter of the Greek alphabet; a form of radiation; a software prototype (4)

���� 28���� Galaxy cluster some 330 million light-years from earth (4)

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