In Britain there has been a postal service since 1657 and an organised series of post offices since 1711. However, if you didn't live near a post office, you had a long walk or ride to post your letters.
In the mid-19th century, a British post office inspector sent to the Channel Islands noticed there were no post offices for people who lived in distant parts of town.
To overcome this inconvenience, he invented the post box, which could be set up anywhere and would be emptied by post office staff on a regular basis. The first was erected on November 24, 1852 in St Helier, in the Channel Islands.
A mere three years later the inventive inspector was to achieve fame with the publication of his first novel, The Warden. Now better remembered as a famous author than as a postal worker, the inventive inspector was Anthony Trollope.
Do different animals have different heart rates? Yes. Adult humans usually have a heart rate of between 70 and 90 beats per minute, but trained athletes tend to have lower heartbeats, even down to 40 per minute. Chil dren usually have a heart rate of between 90 and 120 beats per minute.
In the animal world, some mice have a heart rate of more than 500 beats per minute, while elephants survive on less than 25 a minute and a blue whale's heart beats only 10 times a minute.
Size has a lot to do with heart rate. Small animals lose body heat easily and have to eat a huge amount simply to maintain their body temperature. To produce the energy needed to keep them warm, their hearts have to beat very fast. Larger animals are much more heat efficient, having a low surface area to body mass ratio, so their hearts do not have to beat so fast.