INCHES

• We can cut steel with lasers, but we still give the brightness of a lightbulb as "100 candle-power."
• We can shoot a rocket beyond Saturn, but we still give the output of an engine as "100 horsepower."
• We can spin a bicycle frame from carbon filaments, but we still give its speed as "100 inches."
 
Are these simply balms to soothe the technologized spirit? Even so, haven't you wondered what that "100 inches" is all about?

The bicycle, as it first appeared in the beginning of the 19th century, had no pedals. How slow and awkward this "draught" vehicle must have been, drawn along by action of the rider's feet against the roadway.

More than fifty years went by before pedals were invented, after which the bicycle became what it is today, a "locomotive." Pedals lifted the rider's feet from the ground, and speed increased somewhat. Pedaling rate set the limit in those early days. It still does. You can only crank those pedals so fast.

Early designers found that for a given pedaling rate, higher speeds could be achieved by making the drive wheel larger. Thus, the high wheel bicycle was invented. Better known as the "ordinary" in the 1880s, the bicycle grew in size and picked up more speed -- the limit this time determined by the length of the rider's legs.

Ordinaries were often custom-made to fit the rider like a pair of shoes. Wheel diameter became an important specification. It was traditionally given as the first name in identifying a particular bicycle: 52-inch Rudge, 56-inch Victor Roadster, and the largest ever built, the 64-inch Columbia Expert. The back wheel, meanwhile, shrank away to save weight.

The machine was fast and majestic. It was also dangerous and unforgiving.

Along came the chain-and-sprocket drive. The pedal crank was taken off the front fork and given an axle of its own in the middle of the bicycle frame. Propulsion came from the rear wheel by means of the chain. It was 1890, and the "safety" was born.

A few early safeties were actually built with a large wheel in the rear. Soon somebody noticed that the sprocket on the pedal crank and the sprocket on the drive wheel did not have to be the same size.

For example, the bicycle designer might consider putting a large sprocket on the pedal crank and a small one on the rear wheel. There was an advantage in doing so: to be fast, the bicycle didn't need a big drive wheel anymore.

The speed of the safety depended more on relative sprocket sizes than on the diameter of the drive wheel. The rear wheel then shrank back down to about the size that we see on today's "safety."

Our question is still pending: What about those "100 inches?" We're coming to that.

Some unit was needed to specify the "speed" of the safety. It wasn't so obvious anymore. One couldn't tell very much from wheel size. Measuring sprockets was unhandy and not meaningful -- particularly to long-time riders of the traditional, high-wheeled machines. What could be better, somebody must have thought, than expressing the safety's speed in ordinary terms? That's what the "100 inches" means -- the equivalent wheel size of an ordinary bicycle.

You might like to figure this out for your own bicycle. First, count the number of teeth on your front sprocket. Let's suppose you get 36. Divide that by the number of teeth on your rear sprocket, 12, say.

Now multiply by the diameter of your rear wheel, which is usually 27 inches. The result, 81 in this example, is in inches. It represents the wheel size of a nineteenth-century ordinary, equivalent in speed to your bicycle.

The modem ten-speed safety offers the rider a dynamic selection of sprocket combinations, representing various ordinary wheel sizes, which range from under 20 inches to over 100 inches -- larger and faster than the highest ordinary ever built.
 

Felicitations to the originator of the "Auto-Way" idea.

It is high time bicyclists acknowledged the needs of automotive transportation in our towns and villages.

Cars have become important to many of our citizens -- an expensive but surprisingly popular alternative to the bicycle. Some people in fact, have given up riding their bicycles altogether.

What would be more reasonable, therefore, than to encourage the shared use of the nation's bike-ways?

Putting up "Auto-Way" signs here and there is an inexpensive way to start the program.

A 19th century cartoon shows a harried homemaker washing clothes in a tub, with small children underfoot -- while his wife rides away on her bicycle. The caption: "Don't get the clothes too blue."

Then as now, the bicycle was much valued by women. There were good reasons. Long before what we have come to call women's liberation, the bicycle was availing them with fresh opportunities. By the '90s, the safety with its chain drive and small wheels had become a robust and hassle-free mode of personal transportation.

Women bicyclists gained release from restrictive styles in clothing, bonds of prudish deportment, and the lopsided confinement of housewifery.

Today's unfettered woman seeks fulfillment in business, politics and the professions. She wouldn't dream of sentencing herself to prolonged daily imprisonment and stultifying boredom inside an automobile.

That's why you see so many of the best women in town -- those who really care about themselves -- gliding off-down the road merrily a-wheel.

Recommendations have been voiced by bicycling zealots that top-heavy pickups, macho vans, and stud-tired stationwagons should be banned to protect our roads.

Now, it is true that the nation's original highway paving laws were enacted in the 1880s specifically in response to the needs of bicyclists -- before there were any motorized wagons.

Nevertheless, it is also true that bicyclists have, along with a noble heritage, a most harmonious tradition -- one which compels all riders of wheeled vehicles to live in peace with the environment and with all who share our roads: pedestrians, pets, wildlife, and even those smelly intruders who often come honking along.