A girl's first period can happen anywhere between the ages of 8 to 16. Once it starts, it will come back about once every 28 to 32 days. In the beginning, your period might not be this regular.. You might skip a period, or have two that are only a couple of weeks apart.
In the case of Albert Einstein, he used Hypnosis to access the deepest depths of his creativity, and it was in a Self Hypnosis session that he came to his famous âE=mc2â³ revelation.
The first true hypodermic syringe was created by Alexander Wood in 1853. He modified a regular syringe, which at that time was used for treating birthmarks, by adding a needle. He then used this new device for introducing morphine into the skin of patients who suffered from sleeping disorders.