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 background prepared Bell for work with spoken sound waves and electricity. He began his experiments in 1873-1874 with a harmonic telegraph, following the examples of Bourseul, Reis, and Gray. Bell's designs employed various on-off-on-off make-break current-interrupters driven by vibrating steel reeds which sent interrupted current to a distant receiver electro-magnet that caused a second steel reed or tuning fork to vibrate.