7A

WORTHBASE

RUMIT

FIGURE 5,8-5

Runit Base Line

Observing procedure consisted of adjusting the intensity of the
station lights to the minimum which could be observed and thereby obtaining a small target, considering the distance involved. This was done
as early in the evening as sufficient darkness was obtained, and from one
to three sets of six positions each were observed. Because of weather,
it was sometimes possible to complete only one satisfactory set in an
evening. Usually, from two to five hours each evening were spent in
observing. When results obtained were within the specifications of the
U. S, Coast and Geodetic Survey, no attempt was made to obtain further
refinement.
The strength of figures obtained for the original portion of the

net was an RI of 74.4 with a maximum of 130 allowed.

A maximum triangle closure of 2.5 seconds and an average closure

of 1,3 seconds were obtained,

This compares with a maximum of & seconds

for one triangle and 3 seconds for the average closure allowed by specifications.
Because of the configuration of the island, the Runit Base Line
was a broken base consisting of four sections connecting the stations
North Base and Runit. Traverse Station Runit, used as an angle point in
the Task Force Seven Survey, was again used as an angle point in the

traverse for the H & N Survey.

(See Figure 5,8-5.)

Standard procedure of the U. S. Coast and Geodetic Survey for
second order base line measurement was used. Angles were measured with

5-65

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