Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: MONDAY, November 1, 1993 TAG: 9311010120
SECTION: VIRGINIA PAGE: C-1 EDITION: METRO
SOURCE: Ray Reed
DATELINE: LENGTH: Medium
A: These sound like questions from someone who leads Scout troops on hikes through strange woods.
To the first question: 7 degrees 15 minutes west. Recently, the declination has been changing about 6.1 minutes west per year for the Roanoke area, according to the U.S. Geological Survey. (That's not enough to excuse getting lost.)
Question 2: A compass reading's variation from true north depends on where you are. There's a line of zero declination just west of the Mississippi River. It's called the Agonic line, perhaps because it's agony keeping up with the movement of this changing magnetic line.
The reading also varies as you get closer to the North or South pole. The greatest declination in the United States is 26 to 27 degrees in Alaska. At the North Pole, it's 77 degrees, but that becomes meaningless on a compass, because one definition of the magnetic pole is a place where there is no direction.
True north is defined by the North Star.
As for mineral deposits, local surveyors - who use some magnetic instruments - aren't aware of anything big enough to affect a hand-held compass.
There are some ferrous metals around that can influence magnetic readings if the compass is close to them. Iron often shows up as orange or yellow in rocks; fillings in our teeth contain silver; pickup trucks have enough iron to pull the reading on a magnetic instrument if they're close by.
The conclusion: A compass should point us to true north if we allow 7 1\4 degrees west, hold it away from our belt buckle and keep our mouths closed.
First-person Heimlich
Q: If you choke, can you give yourself the Heimlich maneuver? V.H., Elliston
A: Yes. But don't waste time; it's better to get help from someone.
Unconsciousness comes fast, so wave your hands to get someone's attention and grab your throat with both hands. That's the universal choking signal.
To do the Heimlich on yourself: lean over a chair with its back between your belly button and rib cage until you spit up the foreign object. If this doesn't work on the first or second try, make another effort to get help.
You might try dialing 911 yourself, but choking victims normally can't talk, so it might take 911 a few crucial minutes to trace the call and get help to your door.
Thanks to the education department at Lewis-Gale Hospital for this information.
No family relation
Q: I see some articles in the paper by sportswriter Scott Blanchard. I wonder if he's related to Doc Blanchard, the great football player at West Point in the 1940s? S.M., Roanoke
A: Scott Blanchard, who apparently has been asked this question before, replies, "The long answer is, ever since my dad served in the Navy, family relations have never been the same."
The true answer, though, is, "No, we're not related."
Got a question about something that may affect other people too? Something you've come across and wondered about? Give us a call at 981-3118. Maybe we can find the answer.
by CNB