The Manila hemp is derived from a species of banana originally from the Philippines, whose fibers are tough. The hemp is then used during the paper making process, similar to how Kraft paper uses wood pulp. So the mystery is solved, the manila envelope gets its name from the hemp in which it is made from.
The first modern coin-operated vending machines were introduced in London in the United Kingdom in the early 1880s, dispensing post cards. The machine was invented by Percival Everitt in 1883 and soon became a widespread feature at railway stations and post offices, dispensing envelopes, postcards and notepaper.
The speed of light in a vacuum is 186,282 miles per second (299,792 kilometers per second), and in theory nothing can travel faster than light. In miles per hour, light speed is, well, a lot: about 670,616,629 mph. If you could travel at the speed of light, you could go around the Earth 7.5 times in one second.