Aquapac
Aquapac is a registered trademark and brand name of a UK-based manufacturing company, Aquapac International Limited, specializing in waterproof cases and bags. The privately owned company was formed in 1983 and holds patents worldwide on systems for sealing bags and cases. The range commenced with a waterproof case for the original Sony Walkman known as the ‘Aquaman’, followed by cases for handheld VHF radios. Following Motorola’s invention of the first cellphone Aquapac launched the world’s first waterproof cellphone case. Nokia was an important customer for these cases during the 1990s, as were cellphone operators such as Deutsche Telekom and NTT DoCoMo. Aquapac went on to launch waterproof cases for other handheld electronics such as cameras and eReaders. The company operates out of factories in London, England.
Invention of the telephone
This primitive telephone was rapidly improved. The double electromagnet was replaced by a single permanently magnetized bar magnet having a small coil or bobbin of fine wire surrounding one pole, in front of which a thin disc of iron was fixed in a circular mouthpiece. The disc served as a combined diaphragm and armature. On speaking into the mouthpiece, the iron diaphragm vibrated with the voice in the magnetic field of the bar-magnet pole, and thereby caused undulatory currents in the coil. These currents, after traveling through the wire to the distant receiver, were received in an identical apparatus. This design was patented by Bell on January 30, 1877. The sounds were weak and could only be heard when the ear was close to the earphone/mouthpiece, but they were distinct.