1 янв 1796 г. - 1796 England
Описание:
Edward Jenner noticed that the milkmaids only showed symptoms of cow pox by spots on there hands. He also noticed, if they got small pox they wouldn't receive small pox. Jenner discovered that cow pox can be given as a weakened form of small pox.Добавлено на ленту времени:
Дата:
1 янв 1796 г.
Сейчас
~ 228 г назад
