This Tuesday, Andrew Engel visited class 7b. Andrew is an old scholar of the school and was himself in class 7 in 1952. 

He read to them a couple of exerts from his diary from when he was in class 7 that matched the date around his visit: 

"Monday 4^th February: School as usual"
"Tuesday 5^th February: School as usual; visitor in class gave us a puzzle"
Wednesday 6^th February: School as usual, Death of  King George VI , 2nd violin lesson, weather dull and cold". 

He set the class a puzzle that he was given at their age: "Problem: 9 metal balls, all feel and look the same, one is slightly heavier, but you can not feel the difference. Question: You have a balance scale, what is the smallest number of weighing's you need to do, to discover the heaviest ball?"

He then talked about his career. Andrew went on to study physics at Imperial College London, and then undertook a PhD there. He discussed his career in Astrophysics, and how he worked on an instrument as part of the 'cosmic ray physics group' thats measuring equipment was put into a joint European satellite project. He then later moved into x-ray astronomy and worked with high altitude ballons in collaboration with universities in Australia and Brazil.