1 Calories Burned For Walking: 4.6 km/h (13 minutes per km). 2  Calories Burned For Walking: 4 km/h (15 minutes per km). 3  Calories Burned For Walking: 3.15 km/h (19 minutes per km).
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.
The first electric toothbrush, the Broxodent, was invented in Switzerland in 1954. As of the turn of the 21st century, nylon had come to be widely used for the bristles, and the handles were usually molded from thermoplastic materials.he bristle toothbrush spread to Europe, brought back from China to Europe by travellers. It was adopted in Europe during the 17th century. The earliest identified use of the word toothbrush in English was in the autobiography of Anthony Wood, who wrote in 1690 that he had bought a toothbrush from J. Barret.