Touch-screen smartphones are great, but placing calls hasn't always been so easy. Telephones were once bulky, time-consuming and rare. Before the age of satellites, phones had to be joined by electrical wires. Just how far communications have come is displayed in a new exhibition on the evolution of telephones in China over the past century. It's in Sheung Shui, but well worth the trip. It showcases 66 old telephones and other telecommunication relics from the collections of the China Telecom Museum in Beijing and private Hong Kong collectors. One of the highlights is a 19th century telegraph. The wood-and-iron machine was China's first ever. Liu Pei, curator of the China Telecom Museum which provided many of the models on display, says before the spread of long-distance telephone services, telegrams were the only means to communicate. They were even used to seal business deals. Yet trained technicians were needed to send and receive telegraph messages on the machines in Morse code. One tapped in messages at one end, another translated codes back into text at the other. Though seemingly old-fashioned, telegraphs still have their uses, particularly in field explorations and for military purposes. 'Even the most skilled operator could only produce 20 Chinese characters per minute,' Liu said. 'But the Morse telegram has many advantages: it's simple, easy to maintain and highly reliable. Telephones evolved into the handheld variety over a half century. The earliest models had only a single hole for both sending and receiving sound, and an operator connected the caller and the receiver. Later phones came with speakers and microphones, but a reel had to be cranked to generate power. By the 1940s, the legendary rotary dial had arrived, allowing users to call each other directly. Military needs often drove innovation. The exhibition showcases three first-generation mobile communication devices used in combat during the second world war. One, the first 'handie-talkie', is a wireless, brick-like radio phone used by the US Army. It was the model for today's portable phones because it did not have to be joined to a telephone wire. Much smaller than earlier models, it fitted into a soldier's bag and no longer had to be carried on the back. This phone had a long signal range. Landlines were no longer needed between two devices, as with earlier battlefield models. China's own army once used this model. 'On the battlefield, the first task is to gather accurate intelligence and report it back to commanders quickly,' Liu said. 'Combat units that could communicate any time without having to worry about wires which could easily be damaged enjoyed a battlefield advantage.' Also on display at the exhibition are three replica models of the very first telephone developed by Alexander Graham Bell and phones used in Hong Kong over the past three decades. The exhibition is on at Landmark North in Sheung Shui until October 17.