CLUES AND COLUMNS

1 Who introduced the use of mercury into thermometers? (10)

2 In frequency, what is equal to one quintillion hertz? (8)

3 Bitter in large quantities and prepared from toluene, which synthetic, white, crystalline powder is 550 times as sweet as sugar cane? (9)

4 What is a variable electrical resistor? (8)

5 Which branch of astronomy focuses on the Moon? (10) 6 What is the ‘north star’ also called? (7)

7 In Greek mythology, which son of Apollo became the god of medicine? (9)

8 What genus are any of the Australian trees or shrubs of the Myrtaceae family? (9)

9 The Ob, Yenisei, Pyasina and Taimyra all flow into which body of water? (4,3)

10 Who, in 1932, won the Nobel Prize in Physics for his work in quantum mechanics developing the uncertainty principle? (10)

11 In which period were metals first used to make tools and weapons? (6,3)

12 What is the small rodent now only found in domestication, used variously as a pet, a food or a laboratory animal? (6,3)