12 JULY 2008, Page 71

A fortnightly column on technology and the web

Alongside the vast fuel tank which powers the Space Shuttle into orbit are two spindly tubes known as Solid Rocket Boosters (or SRBs). Their shape is not ideal: their manufacturer, a firm called Thiokol, had intended them to be fatter, but was constrained by the width of a horse’s rear end.

It appears that Roman chariots arrived at a standard axle width of 4’ 81/2” for the simple reason that this width could accommodate two horses’ bums between the shafts. Standardisation of axle length was vital, as on muddy roads your wheels formed ruts that set solid in dry weather. A vehicle with a nonstandard axle can become fatally cross-rutted, a danger for off-road drivers even today. So the 4’ 81/2” standard became literally entrenched.

Axle-makers maintained this length for the next couple of millennia, even into the railway age (helped by the fact that many early rail carriages were adapted road vehicles). A few years later, Britain’s pioneering role in railway development saw the gauge gain hold in the United States, where it influenced the dimensions of railway tunnels. And since SRBs need to be ferried to the launch site by rail, their diameter had to be reduced to allow them to pass through tunnels between Thiokol’s plant in Brigham City, Utah and Florida. So NASA rocketry found itself subject to a standard first adopted in the age of the horse. This story is regularly used to illustrate how adopted standards, however arbitrarily devised, may have massive consequences long after the original reasons for their adoption have become irrelevant.

There are many more such cases, the most famous being the sub-optimal QWERTY layout of a keyboard originally intended to avoid key-jamming in mechanical typewriters. Similarly, the size of a CD was chosen simply so that CD cases two abreast could sit on retail shelves recently vacated by LPs.

But it is important to remember that even a bad standard can be better than none at all. While VHS was generally inferior to Betamax, its eventual dominance was good news for video rental, since stores could stock a decent range of films without doubling up on formats.

Besides, if you really want to see the value of adopting an agreed common standard, simply compare men’s formal wear with women’s. Men have arrived at an efficient, standardised approach to a wardrobe which achieves high levels of interoperability between clothing items: you won’t hear a man say, ‘Ooh, I don’t think this dark suit quite goes with these black shoes.’ Women have no such luck, which is why a chap can be halfway through his second pint while his wife’s still looking for the matching slingbacks. Even women’s clothing sizes are non-standardised — as in the absurd phrase, ‘Monsoon do a very generous 12.’ While women spend hours in changing rooms, I can buy a year’s clothes in the time it takes to say, ‘Ten more shirts like this, please, Bob.’ So when people talk about ‘open common standards’, please remember that this is not jargon. It really, really matters. In 2005 Ned Harrison published a paper suggesting the South lost the US Civil War on account of incompatible rail gauges hampering supplies. Today, if you are ever tempted to claim European co-operation is an unqualified disaster, look at your mobile phone and remember the three letters GSM.