The Straight Dope: Was standard railroad gauge (4’81⁄2”) determined by Roman chariot ruts?

[Send questions for Cecil Adams: cecil@straightdope.com](mailto:cecil@straightdope.com) FOLLOW CECIL ADAMS ON [TWITTER]( AND [FACEBOOK](! [000218.gif] THREADSPOTTING: THE BEST OF THE STRAIGHT DOPE MESSAGE BOARD — 12/13/2019 The proletariat would like a word with you, comrade. [Click here]( for more. STRAIGHT DOPE CLASSIC #1 — 02/18/2000 Dear Cecil: I recently was sent this interesting story by an Internet friend. Is this true? — Dave Shorr Cecil replies: Nothing I like better than getting to the bottom of some well-known bit of netlore. Dave attached the following, which has been making the E-mail rounds over the past year or two: The U.S. standard railroad gauge (distance between the rails) is four feet, eight and a half inches. That’s an exceedingly odd number. Why was that gauge used? Because that’s the way they built them in England, and English expatriates built the U.S. railroads. [Click here]( for more. STRAIGHT DOPE STAFF REPORT — 11/23/2000 Dear Straight Dope: You know those pen size red laser pointers? They are really low power, I know, and don't hurt the eyes perceptibly, but can they cause damage to the eyes over time? How long would you have to shine it in someone's eyes to cause damage and what would that damage be? I heard somewhere about a guy who used one at a girls' hockey game to come on to the girls by shining it in there eyes while they played. Apparently he was charged with assault and battery, but maybe other reasons factored into the charge. Anyway, what's the story on the safety of laser pointers? — Jackson Thayer SDStaff Czarcasm replies: According to my research, some laser pointers are safe — up to a point. Reassuring, isn’t it? The majority of the laser pointers used in the U.S. are Class 3a diode lasers in the 630-680nm wavelength (translation: your garden-variety red laser), with a maximum output of between 1 and 5 milliwatts. Here’s where it gets a little tricky. [Click here]( for more. STRAIGHT DOPE CLASSIC #2 — 02/08/1991 Dear Cecil: Since she was a child, my mother has had something my family calls "perfect pitch": give her the name of a note — E flat, for instance — and she can hum it perfectly every time. Though the women in our family (for six generations!) have had a definite musical talent, we know of no one else who has this knack. What is this thing, anyway? How did she get it? And what can she do with it? — Elisabeth E., Chicago Cecil replies: Perfect pitch, to hear musicians who don’t have it describe it, is a little like being able to make your ears wiggle — a cute stunt, but without much practical value. Others, however, say that having it is like going to color TV from black-and-white. Having looked into the question I am inclined to the latter view. I spoke to several individuals with perfect pitch and though they were all pretty nonchalant about it I found at least some of them could do things that were the musical equivalent of a 360-degree slam dunk. [Click here]( for more. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - [View this message as a webpage](. All trademarks are the property of their respective owners. To advertise on The Straight Dope, contact Rich Hummel at rhummel@suntimes.com [Privacy Policy/Terms of Use]( • [Unsubscribe]( © 2019 Straight Dope, LLC. 30 N Racine Ave. Suite 300, Chicago, IL 60607