Invitees to Lignacite's annual lecture last Thursday at Swiss Re were luckier than many who tried to get into the 'erotic gherkin' at the weekend as part of London Open House. Hordes were turned away as the building proved a victim of its own success (Astragal's informant arrived on Saturday, five minutes after the building opened, to find queues stretching the length of Leadenhall Street). The lecture was also oversubscribed, but all those who signed up were allowed in, and enjoyed the event on the 17th floor and then a reception at the top. For some reason, staff wouldn't let visitors drink wine out of tumblers when the glasses ran out, and they also tried to restrict access to the top-floor bar when they decided it was 'full'. Perhaps they were worried about the structure. But with Ken Shuttleworth as one of the speakers, they wouldn't have had to go far to seek reassurance.