The Prairie Style House: Spatial Diffusion of a Minor Design

The spread of the Prairie style house was'investigated in order to exemplify the means of diffusion of minor'designs. This style, developed by Frank Lloyd Wright, spread'beyond suburban Chicago between 1900 and 1917. It is confined'primarily to selected communities of the Midwest in which its low'elongated silhouette reflects the often flat prairie terrain. The'chronological sequence of diffusion of the Prairie style was'compared to the sizes and rates of growth of the places to which it'spread. This sequence did not conform to a hierarchal pattern'because the style failed to gain acceptance among the elite of'Chicago and other large cities. Prairie design was confined'primarily to middle class circles and spread by means of a'fragmentary system of inter-city communication. Third parties'frequently provided the initial means of contact between architects'and their out-of-town clients. The relationship of third parties to the'architects was often in the role of former patrons. Their ties with'out-of-town clients usually resulted from family or business'associations.     

Laboratory evidence of the use of metal tools at Machu Picchu (Peru) and environs

An interpretation of use-wear marks on metal artifacts is developed from the principles of metal cutting and brittle fracture and applied to surficial markings and microstructural damage on bronze tools from Machu Picchu and environs. Most of the tools have blunt edges, relatively low tin contents, and were not work hardened before use; they appear to have been designed for work that involved breaking chips from hard, brittle material. Use-wear marks on these tools are interpreted as due to sliding contacts and impacts with rock. One tool with a relatively sharp edge has a higher alloy content than those with blunt edges and has been work hardened; it appears to have been designed for cutting wood and use-wear markings suggest it was so used. A long bronze bar carries markings that suggest use by stonemasons. Many of the tools are broken and study of their microstructures shows that the bronze used has poor mechanical properties because of porosity and bands of sulphide inclusions.