Wrinkled and skinny at first, the jellyfish-shaped balloons that Google released this week from a frozen field in New Zealand's South Island hardened into shiny pumpkins as they rose above Lake Tekapo, passing the first test of an ambitious scheme to get the planet online.

It was the culmination of 18 months' work on what Google calls Project Loon, in recognition of how wacky the idea may sound. Developed in the secretive X-Lab that came up with web-surfing glasses, the inflatables beam the internet down to Earth as they sail past. Still in their experimental stage, the balloons were the first of thousands that Google eventually hopes to launch 12 miles into the stratosphere to bridge the digital divide between the 4.8 billion in the world unconnected to the internet and their 2.2 billion plugged-in counterparts. If successful, it might allow countries to leapfrog the expense of laying fibre cable, dramatically increasing internet usage in places such as Africa.

The first person to get Google Balloon internet access last week was Charles Nimmo, a farmer and entrepreneur in the small town of Leeston, New Zealand. He found the experience a little bemusing after he was one of 50 locals who signed up to test a project that was so secret no one would explain to them what was happening. Technicians came to the volunteers' homes and attached to the outside walls bright red receivers the size of basketballs and resembling giant Google map pins.

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Mr Nimmo got the internet for about 15 minutes before the balloon transmitting it sailed on past. He is among the many rural folk who can't get broadband access, and bills from his satellite internet service can exceed £600 in a month.

Google's balloons fly free and out of eyesight, scavenging power from solar panels that dangle below and gather enough charge in four hours to power them for a day. Far below, ground stations with internet capabilities about 60 miles apart bounce signals up to the balloons.

Each balloon would provide internet service for an area twice the size of New York City, and terrain is not a challenge. There are plenty of catches, including a requirement that anyone using Google Balloon internet would need a receiver plugged in to their computer to get the signal. Google is not talking costs at this point, although it is striving to make them as low as possible.

Before heading to New Zealand, Google spent a few months secretly launching flights in California, prompting a handful of unusual reports in local media. "We were chasing balloons from trucks on the ground