INDIAN AMERICA 249 
structures were directly proportional to the respective water 
resources of each area. 
In the semi-arid and broken highlands, the Indians built huge 
systems of irrigated farming terraces. The beginning of terracing 
for agriculture may go back to before the time of Christ, but it 
seems that its maximum expansion took place in Inca times. After 
the Spanish conquest the terraces were neglected and most of them 
fell into ruin. 
Applications of Archaeology 
Dr. Whyte called attention to the need to ‘‘map the cultivated 
lands in relation to their farming systems and the crops grown 
thereon” (p. 182). I suggest that this study must be made within 
the historical context. In many zones the knowledge of the past, 
the local story of trial and error in land management, might help 
in planning for the future. 
Dr. McClellan asks for sociological and economic research keep- 
ing pace with engineering and scientific research (p. 198). Anthro- 
pologists have explored the relationships between technical change 
and society. Man is a social animal and the alteration of the bal- 
ance between technology and the societal forms, through induced 
changes of the first, tends to start chain reactions which are as far 
reaching in their effects as those resulting from the alteration of 
the ecological balance in nature. This is to be kept in mind by 
those who have the responsibility of planning the future of arid 
and semi-arid lands and of the people living on them. 
Furthermore, there is the problem of acceptance or rejection. 
In underdeveloped areas where people live in traditional ways it 
is absolutely necessary to bear in mind the cultural situations in 
any project of improvement. Only under that condition will it be 
possible to guarantee the social acceptance of the technical im- 
provements which have to be introduced. It 1s a principle well 
established in cultural anthropology that whatever may be the 
technica] value of programs of aid, these may run the risk of failure 
if they do not take into account the cultural conditions. 
