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My new hiking tool January 19, 2015

Posted by Jenny in bushwhacking, hiking, history, Life experience.
Tags: , , , , , ,
Actually, it's pretty old... but in this case that's a good thing.

Actually, it’s pretty old… but in this case that’s a good thing, because this is rare and valuable.

Everyone who explores off-trail with me knows that I use map, compass, and altimeter and don’t own a GPS. If you are curious about this preference, please read this piece, which I wrote in late 2008. That was toward the end of my long sojourn in New England, so you will find references to oddities like the severe magnetic declination in the Northeast.

At that time, I still owned an analog altimeter. It was a Peet, the second one I owned. An earlier Thommen had been lost. The Peet got drowned after I returned to the Smokies area and waded up Lester Prong (I’ve also drowned a camera there). And I found that I was unable to replace it, due to the now-complete dominance of digital devices of one sort or another. All I could find on the market was crude altimeters with very large increments of elevation, some meant for skydiving. Because smaller means more precise, you don’t want anything more than 20′ increments.

I’d also been using a digital altimeter on a lot of hikes. I do like the multiple functions of these devices, the ability to do things like get your cumulative elevation gain or fun-but-totally-unnecessary things like set an alarm to go off when you’ve reached 4000′. But they have never been as accurate as the mechanical altimeters.

So I reluctantly accepted that the older ones were extinct, and I’ve gone through several digital altimeters. They always seem to start going wonky well before the battery dies, and they are severely affected by temperature. Check your wristwatch altimeter in a warm car just before you get out into near-zero temps, then check it again. You’ll see what I mean.

In the meantime, GPS technology just keeps getting better and better. I remember folks trying out the early models in the mid-1990s and practically heaving them into the woods with frustration, often for lack of satellite coverage.

I don’t hate GPS units or think they’re “cheating” or somehow inferior to traditional technology, though I do believe that everyone who uses a GPS should also know how to use map, compass, and altimeter in case something goes wrong. A compass never goes wrong unless you’re in weird magnetic terrain or unless the compass becomes mechanically broken (that did happen to me with a 25-year-old compass). My only other hesitation about GPS use is that folks sometimes seem to look at the unit more than they observe the terrain.

I admire the wonderful tracks and maps that people produce with GPS and associated software. And I see how GPS is especially useful for people pinpointing very specific locations such as old homesites.

Anyway, there was recently a discussion about all this on the “GoSmokies” forum. I put in my typical comment about my method of navigation: in the Smokies I use altimeter more than compass to locate points like specific stream junctions where I know the elevation. At the end of my comment, I mentioned that if anyone had an old analog altimeter, I’d like to buy it. And someone responded! A very nice guy named Dan G. was willing to part with an old but top-of-the-line Thommen altimeter.

I immediately wondered if it had the wonderful feature of my old Thommen: a small window that changes color each time the needle makes a circuit of the 3000′-dial. A little below 3000′, it shows red to alert you that you’re moving up to the next circuit; below 6000′, it shows yellow; below 9000′, it shows blue, and so on. And it DID have the window, plus some features related to units of barometric pressure that my old one didn’t.

You may ask what’s so wonderful about a little window that shows color. Well, it’s because the dial can’t show more than 3000′ since any larger amount of elevation would take up too much space. Suppose you could see up to 10,000′ with one revolution of the dial. Can you imagine how small the markings would have to be—or how large the dial would have to be?

I know, so much easier to have a rectangular screen with numbers that change digitally. But you miss out on the beauty of a complex and ingenious mechanical device. And…it has no battery. Hah!

Closeup of the small window.

Closeup of the small window.

In the photo above, you see red disappearing to the left and a tiny bit of blue coming up on the right. We are a little more than two-thirds between the 0 and the 3 because the photo was taken at my house, which is at elev. 2160′. You can see that in the top photo.




1. Clyde - January 19, 2015

Jenny, wish I had known you were looking for a Thomen. I have one. I like the wristwatch version better since it is so handy. You are right on knowing how to navigate without a GPS. I hiked for 5 or 6 years off-trail before I bought my first one. It is a great excuse to stop for a minute to look at it! That way I don’t have to admit I want a short break! I just say let’s check the nav aids!
I don’t remember the altimeter doing anything funny the day Frank and Mike and I did Allnight ridge. And it was 2 when I got out of the car. That said, it was an easy navigation day and I wasn’t looking close at altimeter or GPS.

Jenny - January 19, 2015

Please keep that Thommen, Clyde! You never know when I’m going to destroy another altimeter—though I’m sure going to try hard not to do that with this one. Regarding temperature differential, you of course are saying it was two degrees when you got out of the car (I remember your telling me that; otherwise I might misread your sentence as “it was two o’clock.”) All I can say is that I’ve seen the elevation change 200 feet in that situation, with a digital wristwatch altimeter, not with an analog altimeter. They are temperature-compensated, though I can’t claim to understand how that is done.

2. Doug Borton - January 19, 2015

As an old flight instructor, I’ve always thought carrying an analog altimeter would be fun, and informative, while hiking.
I do have one comment though. At the end of your piece, when referring to an altimeter, you state that it has the “…beauty of a complex and ingenious mechanical device.” I would suggest that the beauty of this ingenious device is in it’s simplicity. The mechanics of the altimeter are actually very simple. That’s not to say that they can be cheaply made. As you know, well made altimeters are pricey.

Jenny - January 19, 2015

I see your point, Doug. And you certainly know much more about it than I do. As I understand it, the altimeter is essentially the same as an aneroid barometer. The principle is one of an internal part contracting and expanding according to changes in barometric pressure. That principle does seem quite simple and straightforward. But constructing a device to transfer that contraction and expansion into the movement of precise gears that turn the needle on the dial seems a bit mind-boggling to me. 🙂 Perhaps it’s that elusive concept of “elegant simplicity” that gets at what I have in mind.

3. Hoover - January 20, 2015

Hi Jenny. Glad you were able to be reunited with the technology of your choice! I understand completely. I don’t hate new technology, but I do see a lot of it that is more complex and more expensive yet does nothing new or better than the old tech. (BTW, have you thought about taking up skydiving?) Also, when you mentioned hikers looking at their GPS instead of the terrain, I visualized a family at a restarurant, all of them looking at their phones instead of talking with each other.

Jenny - January 20, 2015

Now, there’s a great comparison! Our technological tools seem to mesmerize us, one way or another.

4. Gary Howell - February 7, 2015

Sounds like nIce hikes lately .. I of course am even more primitive (usually no compass, never an altimeter, occasionally a map). My cotton clothes and slick shoes soles aren’t always too great either. Have been a bit confused sometimes.

I was grateful for a compass when we got out of Loran range on the way to the Bahamas, the wind had snapped a stay on the mast so we had to take the sails down, waves high enough that the motor came out of the water a few times every minute, finite supply of gasoline ..

Jenny - February 7, 2015

Now, that sounds like a hairy situation!

5. MIKE DESIMONE - February 7, 2015

Jenny, I found this piece fascinating. My entire life changed when I discovered an altimeter (thanks to Bob, of course). Don’t remember much about my first one. I had it for a short time and lost it on Mt. Ellen. I then bought my first Avocet and had it for 12 years. I bought a second Avocet in 2008, this one with 5-foot increments. It’s proven very accurate. I’ve also noticed on multiple occasions that the elevation gain would be exactly the same measurement on the same peak even though hiked years apart. Soon I was carrying it on bike rides and x-country skis.

6. Patrick Barry - September 3, 2015

I just picked up a Thommen second hand here in New Zealand and couldn’t find any information about how to read it until I found your article. Thanks!

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