My worst nightmare

Back from a field trip, I found an email from my MPhil student's external examiner saying he would be in Portsmouth that day. The student had arranged the viva behind my back. I rang her in London to say she had three hours to get down here. She got the slow train, failed to change and ended up in Bognor Regis. To fill in three hours, I took the examiner to lunch and on a departmental tour, including the new toilets.

David Martill is a senior research fellow, School of Earth and Environmental Sciences, Portsmouth University.

• Do you have a worst nightmare? Email mandy.garner@thes.co.uk