Inner-tubes are the inflatable parts between the tire and the metal parts of the wheel. They are invisible apart from their valves that protrude through the wheel-rims. There are three valve types in use; Schrader valves, Presta valves, and the lesser used Dunlop valves. Refer to the adjacent image for examples.
The word papyrus /pÉËpaÉªrÉs/ refers to a thick paper-like material made from the pith of the papyrus plant, Cyperus papyrus. Papyrus can also refer to a document written on sheets of papyrus joined together side by side and rolled up into a scroll, an early form of a book.The plural for such documents is papyri.apyrus is made from the stem of the papyrus plant, Cyperus papyrus. The outer rind is first removed, and the sticky fibrous inner pith is cut lengthwise into thin strips of about 40 cm (16 in) long.
A section of the Egyptian Book of the Dead written on papyrus. Papyrus was first manufactured in Egypt and Southern Sudan as far back as the fourth millennium BCE. The earliest archaeological evidence of papyrus was excavated in 2012 and 2013 at Wadi al-Jarf, an ancient Egyptian harbor located on the Red Sea coast. section of the Egyptian Book of the Dead written on papyrus. Papyrus was first manufactured in Egypt and Southern Sudan as far back as the fourth millennium BCE. The earliest archaeological evidence of papyrus was excavated in 2012 and 2013 at Wadi al-Jarf, an ancient Egyptian harbor located on the Red Sea coast.