In the United Kingdom, prior to 1840 the postal system was expensive and confusing. Letters were paid for by the recipient rather than the sender, and were charged according to the distance the letter had travelled and the number of sheets of paper it contained. Around this time, the postal system was reformed, leading to the invention of the famous Penny Black and the sender paying for the letter. In 1849, the Royal Mail first encouraged people to install letterboxes to facilitate the delivery of mail. Before then, letterboxes of a similar design had been installed in the doors and walls of post offices for people to drop off outgoing mail.
These days, technology is increasingly taking more hold within peoples' lives. You only need to travel on public transport in any given city, and you'll notice people immersed in their own world of mobile phone, headphones or a combination of the two. Rarely do you see strangers fascinated with each other. I often wonder what it must have been like in these cities a hundred years ago; were people more engaged and interested with each other?