Hyperloop at launch festival 0216 Image: Kevin Krejci/Flickr Hyperloop at launch festival 0216 Image: Kevin Krejci/Flickr

Hyperloop is like a litmus test for technology. Its critics are legion. If it can work, then it could transform transportation around the world. But if investor confidence is anything to go by, things are looking promising.

To remind you, Hyperloop is an idea, first proposed by Elon Musk, for an elevated transport system, that travels in a partial vacuum at speeds close to 700 miles per hour.

When Musk first put the idea forward, he envisioned a system linking Los Angeles and San Francisco in a journey time of less than an hour. But now there is talk of many routes, including a hyperloop from London to Edinburgh.

But there is queue of critics, long enough to stretch from Timbuktu to Lapland, of people who say it can not happen, that the technology is not viable, they say that once again, Musk is dreaming, a pipe dream concerning pods in a pipe.

Well, the proof of the pudding is, as they say, in how nice a meal it makes, and investors seem to be eating up Hyperloop One’s business model.

It has now raised another $85 million, bringing the total amount raised so far to $245 million, valuing the business at around $700 million.

That’s a lot money for a company selling snake oil, as the critics claim, its dirt cheap for a company that could revolutionise how we travel.

Shervin Pishevar, Executive Chairman and co-founder of Hyperloop One said: "We are so fortunate that our new and existing investors share our vision of making Hyperloop the world's first new mode of transportation in over a century. We initially targeted $50 million and ended up raising $85 million instead."

And then he made the bold claim. "We've proven that our technology works and that Hyperloop One is the only company in the world that has built an operational Hyperloop system. As we move towards the commercialisation of our technology, we'll continue to work with governments and embrace public-private partnerships to reimagine transportation as we know it."

Back in August, the company successfully tested the technology, achieving speeds of 192 miles per hour for 1,433 feet.

That is not quite London to Edinburgh in less time that it takes to check in at an airport, but it is promising, all the same.