David White Pocket Sighting Level 17-620This level will quickly and easily approximate the
level of retaining walls, batter boards, fences,
etc. For these operations, set a leveling rod,
folding rule, or length of stick on the object to be
checked. Sight through the level (hold level close
to eye and look through small opening at rear of
level). NOTE: Do not cover level vial opening with
your fingers. This will prevent light from entering,
making it difficult to see the bubble. Raise or
lower front end of the level until the bubble is
centered on the long center line on the object
window. Readings can be made easier and more
accurate if a level rest is used. A 1x2 board cut to
a convenient height is adequate.
Determining Differences in Elevation
Place the leveling rod or stick at a convenient
distance. Sight through the eyepiece and with bubble
centered, note or mark reading on rod or stick. For
example: First reading on rod is 5ft. Move rod to
new location and take a second reading. This reading
is 3ft. Difference in elevation between the first
and second reading is 2ft.
Large differences in elevation are determined as
follows:(1)Measure the difference from the ground to
your eye while standing comfortably erect.
(2)Start at the base of a slope and sight through
eyepiece. (3)Mark the spot on the slope where the
level line of the sight shrikes the ground. (4)Move
up to this location and sight again. (5)Repeat same
procedure until the top of the slope is reached.
Total numbers of sightings multiplied by the
distance from ground to your eye totals difference
The distance between the top line and the bottom
line on the object glass is equal to a ratio of
1:12. If the user is looking at a sighting rod and
the top line crosses the rod at 5 ft. and the bottom
line at 4ft. The user is 12 ft away from the rod.
5ft-4ft = 1ft 1ft x 12 =
If the distance is so great that you cannot read the
numbers clearly, have the person holding the rod
point to a starting mark. Tilt the pocket level
until the bottom line crosses the rule at his
finger. Then he can slide his finger up the rule to
where it crosses the top line. He can then give you
the readings and you can determine the distance.
Setting Wall Tiles in a Level Line
Rest the pocket level on a convenient surface or
stand erect holding it to your eye, and sight
through the pocket level at the wall to be tiled.
When bubble is centered on the long center line,
mark wall in line with the long center line. Repeat
this step one or more times along wall. By measuring
up or down from these marks to the height desired,
you have a level starting line.
Setting Fence with Level Top
Drive two poles into the ground, one at each end of
the fence location.
Poles should be tall enough to sight without
stooping over. Rest the pocket level on convenient
surface or stand erect holding it to your eye and
sight on one of the poles. When the bubble is
centered on long center line, mark pole in line with
the ling center line. Repeat on second pole,
sighting from the same position. By measuring up or
down from these marks to the height desired, you
have a level line for the top of your fence.
Grading a Driveway
Establish roughly the ends of the driveway and drive
poles into the ground every ten feet. Poles should
be tall enough to sight without stooping. Sight the
nearest pole. If you are standing at the upper end
of the driveway and desire a 1/4" per foot grade,
center the bubble on the first line below the long
center line and mark the pole in line with the long
center line. Sight each pole in the same way from
the same position. If standing at lower end of the
driveway, use the first line above the long center
line. Drive a stake into the ground next to the
first pole so the top of the stake is at the desired
driveway height. Next, measure from the mark on the
post to the top of the stake. Drive stakes next to
each of the poles and set them so the tops are the
same distance below the mark you established on the
The stake tops now correspond to the grade of 1/4"
per foot. For a 1/2" per foot grade use the second
line above or below the long center line.
Establishing a Slope
For setting grades other than 1/4" or 1/2" per
foot(see above), drive poles into ground at equal
distances every ten or twenty feet or other
convenient distance. Rest pocket level on convenient
surface or stand erect holding it to your eye and
sight the first pole. When bubble is centered on the
ling center line, mark pole in line with the long
center in line. Sight each pole the same way from
the same position. These marks are now level. By
measuring an amount equal to the slope required from
these marks, you can establish a line for any slope.
Contour Farming and Terracing
Set a leveling rod or stick at the point where the
furrow will be started in the field. Sight in the
rod or stick and mark the position with a narrow
strip of cloth or target. Drive a stake at this
spot. Move the rod or stick to the next convenient
location. By moving up or down the slope until a
level line of sight hits the cloth or target, the
point along the contour is determined. When a furrow
is plows between the two stake points the elevation
will be the same at both points.