six o'clock in the evening
Besides , the number of houses or flats is very closely proportioned to the number of tenants , and there are never many vacant houses . The members of the Third and higher classes own their own houses , and can therefore change their residences by purchasing or exchanging . By special privilege members of the Fourth Class can obtain permission to buy their houses , but as these are mostly flats they are usually rented from the municipality . Following Conductor Prigge 's instructions , I presented myself at six o'clock in the evening at the entrance to the Great University of Mecco . It was the first time I had been out without my ` keeper , ' but as everybody else was dressed in the Meccanian costume , whilst I was wearing the clothes I had been accustomed to wear in Luniland and Francaria , there was little risk of my going astray . A porter darted out of a box in the entrance hall and directed me to Room 415 , where the Professor of Historical Culture was to deliver his monthly four-hour lecture to Foreign Observers . I found about a dozen Foreign Observers of various nationalities waiting in the small lecture-room , and presently a few more arrived .