Length of a Building
This is your scale drawing of the
base line which you have paced out (e.g.
Scale 1" = 10' (One inch equals 10 feet)
Place markers (say 50 feet apart). This is your base line. Make a scale
drawing of it (5"). At points A and B on the sketch draw in the North point
bearing. Take bearings from North at A for each of the church at X and Y. Take
bearings of X and Y at B. Mark in these bearings on your sketch using a
protractor. Join up line X. and Y between the two points where the lines cross.... If the line
X Y measures 2" then the church is 20 feet long.
It is important to know your own personal measurements. It also can help to
find a measurement on yourself that is exactly one centimeter (maybe a
fingernail width), then also find a 10 cm and a 1 meter measurement.
Remember that Scouts' bodies are still growing so personal measurements
should be checked an a regular basis.
Here are some more ways of making fairly close estimates of height and
distance. You'll be making practical use of some of the basic geometry learned
Have a friend whose height you know stand against the object
for which you want to find the height. Now follow these steps:
1. Hold a pencil or short stick at arm's length, and sight across top of it
to the top of your friend's head.
2. Move your thumb down on the pencil until you sight across it to your friend's feet.
3. Raise your arm until your line of sight over your thumb hits the top of
you friends head.
4. Note where your line of vision across the top of the pencil cuts object to
5. Move your arm up again and repeat step 4.
6. Keep repeating steps 4 and 5, counting as you go up, until you reach the
top of the object.
How many sightings did you take, including the first one friend? That is the number of times higher the cliff is than the height your friend. Multiply
that number by your friend's height to find the height of the object.
Height by Shadow
You might try guessing the height of a tree by using shadow.
1. Get a stick of known length and notch it in meters and centimeter
2. Stand the stick upright in the sun and measure the length of the shadow.
3. Measure the length of the shadow cast by the tree.
4. Multiply the stick
length by the length of the tree's shadow.
5 Divide by the length of the shadow cast by the stick. The result is the
height of the tree. Here is the formula: Tree height = Stick length x tree
1 Stick shadow or Tux ss [?]
For example, if the stick's length is 2 m, the tree's shadow is 20m long, and
the stick's shadow is 5m long:
2 x 20/5 = 40/5 = 8 so the tree is 8 meters high
Line of Sight and a Measured Stick
Here is another method you can use to measure a tree or building:
1. Measure along the ground from the base of the building out far enough so
you can sight the top of the building from ground level at a comfortable angle.
2 Mark this distance off in nine units of equal length say, nine measured
3. Nine stick lengths out from the building, stand your stick upright and
have a friend hold it.
4. Measure off one more unit past the stick.
5. Put your head to the ground and, getting your eye as close to the ground
as possible, sight the top of the building.
6. Where your sighting line cuts the stick, have your friend make a mark.
Measure the number of centimeters front that mark to the ground. This will
closely equal the height of the building in meters This works out to the formula
Estimating the Width of a River
Here is a handy estimating method for Golfers and for groups setting out to
erect pioneering structures.
1: Pick out a point across the river, such as a tree (A).
2. Drive a stake (B) into the ground on your side of the river, in line with
3. Walking parallel to the river bank, make a baseline of any convenient
length, say 40 m.
4. Drive a stake (C) into the ground.
5. Continue along the bank in the same direction for half the first distance
you measured (20 m).
6. Mark the spot D.
7. Make a 90° turn (your back to the river) and walk inland until you can
sight your first stake C in a line with the tree across the river.
8. Mark the
9. Measure the distance between the stakes D and E.
10. Double this distance and you will come close to the actual width
providing, of course, the sighting, measurements and angles are correct.
Learn the exact length of your pace. Try to learn to pace an exact 3 meters
distance with five of your paces (if you do this one kilometer will equal 1665
Remember things can appear nearer or further than they really are depending
on how clearly you can see the outline. Also, if there is water between you and an object, the distance
can be deceptive.
1. Objects seem further away:
(a) When they are in the shade,
(b) Across a valley,
(c) When they are the same color as the background,
(d) In a heat haze,
(e) When you are lying down or kneeling.
2. Objects seem closer:
(a) With the sun behind you,
(b) In very clear air,
(c) When a different color from the background,
(d) When the ground is fiat
(or snow covered),
(e) When it is larger than other objects nearby,
(f) When you are looking across water, or a deep valley.
3. Visible objects seen nearer at night than during the day.
Remember they eye measures distance "as the crow flies', and does not
allow for uneven terrain. In other words actual distance may be greater than