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KC

On 1/8/2015 8:48 PM, wrote:
On Thu, 08 Jan 2015 15:16:28 -0500, KC wrote:

On 1/8/2015 2:19 PM, wrote:
On Thu, 08 Jan 2015 12:24:14 -0500, KC wrote:

On 1/8/2015 12:13 PM, Justan Olphart wrote:
On 1/8/2015 11:05 AM, True North wrote:

I've thought about buying the Davis 25 plastic sextant to play with.
one practical use would be to confirm the height of the huge Linden
trees that border my back yard.
I did a google search and found a link that described how you could
estimate height with an upside down protractor, a string with a
weighted object as a kind of plumb bob and a ruler to sight along.The
ruler would sit on the upside down base of the protractor and the
string would give you the sighted angle. The guy provided the formula
to get a fairly accurate height.

You haven't mastered left, right, up, and down yet. You aren't ready for
a sextant yet.

In the cub scouts we learned to use a ruler held at arms length and a
bit of math to get the height of a tree or anything really.

There are a number of fairly simple geometry tricks to do things like
this. If you have the luxury of choosing your place to shoot the
angle, just use a regular 45 degree drafting triangle and a spirit
level.

Like I said, a 12 inch ruler or a plain old yard stick and your arm..
you need to know the length of your ruler from your eye, and the
distance to the *tree*.. No drafting triangle necessary at all

Just trying to remove the math for people who think trig is hard.

I forgot, we got lib arts students here...