2. The correct version is to ‘rack one’s brain’, as in stretching it to find an answer, while ‘to wrack one’s brain’ would imply a state of decay.
3. A Pasteur pipette is commonly known as a ‘dropper’ or ‘eye dropper.
4. Swahili, Xhosa and Zulu are Niger-Congo languages that belong to its Bantu group.
5. On HMS Beagle’s second voyage, the one referred to in his book ‘The Voyage of the Beagle’, Charles Darwin sailed for the South Pacific on December 27, 1831. The voyage lasted just over 2 months short 5 years, during which time he spent 6 months exploring the Galapagos.