Smallpox 1718. In 1721, Cotton Mather and colleagues provoked controversy in Boston by inoculating hundreds. In 1796, Edward Jenner, a doctor in Berkeley, Gloucestershire, rural England, discovered that immunity to smallpox could be produced by inoculating a person with material from a cowpox lesion. Cowpox is a poxvirus in the same family as variola. Jenner called the material used for inoculation vaccine, from the root word "vacca", which is Latin for cow. The procedure was much safer than variolation, and did not involve a risk of smallpox transmission. Vaccination to prevent smallpox was soon practiced all over the world. During the
Practical joke victimized or humiliated. Thus most practical jokes are affectionate gestures of humour and designed to encourage laughter. However, practical jokes performed with cruelty can constitute bullying, whose intent is to harass or exclude rather than reinforce social bonds through ritual humbling. Some countries in Western culture traditionally emphasize the carrying out of practical jokes on April Fools' Day. A practical joke is "practical" because it consists of someone doing something physical, in contrast to a verbal or written joke. For example, the joker who is setting up and conducting the practical joke might hang a bucket of water above a