The Southwestern Historical Quarterly, Volume 29, July 1925 - April, 1926

THE
SOUTHWESTERN HISTORICAL
QUARTERLY
VoL. XXIX OCTOBER, 1925 No. 2
The publication committee and the editors disclaim responsibility for views expressed by
contributors to THE QUARTERLY
THE EARLY ART OF TERRESTRIAL MEASUREMENT
AND ITS PRACTICE IN TEXAS
EDwIN P. ARNESON
I
Man's curiosity and wants have impelled him to wander about
the earth and to "go down to the sea in ships." To find his way
back he has developed the arts of exploring and navigation, and,
to fix his domain, surveying.
The most difficult of these arts to perfect has been navigation,
obviously because of the lack of fixed objects on the horizon, and
because a ship's deck provides an unsatisfactory support for even
crude nautical instruments. Until the time of Columbus, it may
be said that almost no mariners had ventured out on the open
seas for long voyages, if we except those of the Northmen. The
navigating was largely coastwise. Short voyages were made to
outlying islands by the pilot system; that is to say the ship's com-
pany contained one or more men, who had made the trip before.
On the cloudless Mediterranean sailors had known from remote
times to use the north star for direction. In about the eighth
century of our era the magnetic needle was introduced into Europe
by the Arabs. The more skilled navigators had applied the science
of contemporary astronomy to their needs, and had devised a
method of determining approximate latitude by measuring the
height of the sun at noon. On the sea the measurement was made
by a cross-staff; on land, by the astrolabe. As these two astro-
nomical tools were very important in the charting and exploring of
the new world they merit description.

Texas State Historical Association. The Southwestern Historical Quarterly, Volume 29, July 1925 - April, 1926. Austin, Texas. The Portal to Texas History. http://texashistory.unt.edu/ark:/67531/metapth117141/. Accessed August 28, 2014.