Sincere and heartfelt condolences. I was devstated to hear of Marks passing, and that I did not get to say goodbye to him. He was always the friendly face at the coffee machine, always chatty and ready to talk about anything from childborth to physical chemistry. He was a true expert and I learnt everything I know about ice cream from him. My favourite and most recent memory was when he helped myself and a student identify the chemical composition of a piece of glass that we had broken on a sensor. It bought the fun and excitment of science back to me for a coupe of hours. He really will be very much missed.