Data and Understanding 
LUNA B. LEOPOLD 
United States Geological Survey, Department 
of the Interior, Washington, D.C. 
In the year 1534 when Cabeza de Vaca escaped from the 
aborigines of southern Texas by whom he had been enslaved for 
six years, he made his way on foot from the vicinity of Galveston 
to the west coast of Mexico. Although his Relacién was not 
printed until 1542, the verbal report of Cabeza de Vaca gave 
impetus to the growing interest in exploration of New Spain. 
Estevanico, the black, one of de Vaca’s companions, served as 
guide to Fray Marcos de Niza on the first Spanish reconnaissance 
to reach the village of Zuni in New Mexico. 
The earliest Spanish exploring parties hoped to find riches, but 
expected to acquire, at the least, facts. These “gentlemen of high 
quality,’ as Castafieda called them, wanted to see for them- 
selves whether the cities of Cibola had streets of silver. Hearsay 
was not enough. Rumor was to be replaced by first-hand knowl- 
edge. 
Without discounting the hope for personal gain, these men 
presumably were fired with some further intellectual and spiritual 
motivation, among which must have been the desire for facts 
about these parts where we are assembled. Inscription Rock, only 
a few miles west of Albuquerque, bears illuminating tidbits of 
history. Don Diego de Vargas, says the carved inscription of 
1692, came here “A su costa’’—at his own expense. 
Weare attempting tosurvey and correlatesome of the facts which 
people have gained about the nature of semi-arid lands. We are 
better off than the early Spanish explorers, for in the intervening 
period data and information have been accumulated in scope and 
in detail beyond the imagination of our predecessors. We have 
114 
