The Indianapolis journal., 1904-02-14
The Surveyor and His Tools
Are Agents Of Civilization
Construction and Uses of the Mysterious
body Has Seen and but Few Understand

termining the straight line from his own
rocatlon TO the other mans. When he re-
peats this operation with another objective
Int to look at. the revolution of his tel
escope records on scale the exact angle
through which the instrument moves. and
after the distance from the transit TO each
or the objective points has been measured
with the chain" or steel tape, the sur
Veyor knows one angle of the piece of land
he is measuring and the length OF the lines
mat form It.. The measurement of any
given piece OF land is simply the determi-
nation of all its angles and the length of
the lines that form them. and the success
OF the surveyor lies In his judgment In
choosing his angles and his accuracy in
handling his instruments. 1t is an interest
ing example OF the skill developed in these
student surveys that the results of work
done each year in the summer schools
which the Massachusetts Institute of Tech
nology conducts in places that have pre-
viously been unsurveyed are accepted as
authoritative data by the government ex-
perts at Washington.
Actual land measurement, however, is
only one incident in the work of the trained
modern surveyor. He must know some-
thing of astronomy I'm order to be ready
to establish the latitude of any place in
which he may be working; he must be
able TO determine attitudes, tide levels and
vertical angles: he must possess other frac-
tions of knowledge necessary to make up
the sum total of geographical information
that precedes the building of a railroad,
the digging of canal, the laying out of
a new turnpike or the planning of a big
industrial plant with some local water DOW
er as its first reason for existence.
TRANSIT PRINCIPLE THE BASE.
Most of the different instruments used
for these purposes are adaptations of the
transit principle. There is the alidate, for
instance-roughly speaking, {. ruler with
a sight like a gun. Having sighted some
object whose distance has been determined
the surveyor can, by means of the ruler,
fnl Il a
horizontal to the earth, a straight line rep
resenting that distance on whatever scale
he has selected. The drawing boards used
IN this work are also mounted on tripods
with an ingenious arrangement to hold
them in an exactly horizontal position,
and sufficient number of lines thus es-
tablished and drawn 10 scale on paper
produce an exact map of the territory over
which the surveyor is working.
Another interesting instrument is what
is called a solar transit, which has a sec
ondary telescope that looks ut the sun and
enables the surveyor TO determine when
his regular transit instrument is POINTING,
in north and south direction-an instru-
ment invented TO facilitate modern sur
veying in the great territory of the West
where earlier surveyors fixed many Of their
north and south lines by compass. Now
adayS the compass, with its variations from
the true north. is no longer used on the
most exact work, the engineer arbitrarily
choosing his own initial point. and making
everything dependent solely upon IL
One of the most familiar articles of the
surveyors kit is, of course the striped
pole. sometimes black and white some
times red and white. These poles have n
direct relation to the horizontal markings
with which the kindly spider has supplied
the field of the transit glass. The number
of alternate spaces seen between the hor-
lZOntal lines means distance In feet 10 the
young man who peers through the tele-
scope. and the poles are often fitted with
sliding gauges which enable the distance
10 be read even more accurately.
The Technology equipment includes prac-
tically every variety Of apparatus now en-
ployed. and probably few instruments any
where see more varied service During the
school year they are used by about 200 stud
ents, and In the summer they generally
travel TO some part of the country where
such outfit has previously been an un-
known quantity. 10 be used in making a
thorough and. rs has been said, remarkably
authoritative survey of the region, while
the training obtained with them is likely TO
be taken eventually TO every part of the
United States and its possessions.