|
|
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
In 1844, Charles Goodyear obtained the first patent for a rubber condom.
There used to be a metric calendar, as well as metric clocks. The metric calendar, or "French Republican Calendar" divided the year into 12 months, but each month was divided into three 10-day weeks. Each day had 10 decimal hours. Each hour had 100 decimal minutes. Due to lack of popularity, the metric clocks and calendars were ended in 1795, three years after they had been first marketed.
Oliver Wendell Holmes is credited with introducing the words "anesthesia" and "anesthetic" into the English language in 1846.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
![Children will feel more at ease and have a better learning experience if they are allowed to touch ...](https://biology-forums.com/gallery/47/medium_665046_07_03_17_5_19_36_26492919.jpeg)
![It is difficult to capture the anguish of the children of divorce, but when I read these lines by ...](https://biology-forums.com/gallery/27/medium_482573_20_04_17_12_30_43_27939455.png)