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Abstract

This paper presents inferences based on the results of an experimental project comparing the effectiveness of stone, bronze, and steel axes in felling trees. The study shows that bronze is as efficient as steel for this task, and therefore the two material types can be considered equivalent when comparing technologies. We support the findings of other studies indicating that metal axes are more efficient than stone axes in a number of ways other than effort expended. Other variables that affect tree felling efficiency are discussed. Tree type, tree diameter, and axe type are the most important, but other factors may also be significant. The use of regionally specific estimates for tree felling time is suggested when making cultural inferences based upon experimental data.  相似文献   

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1938年10月24日端纳(W.H.Donald)随蒋介石离开汉口,视察鄂、湘、赣、桂前方阵地,12月前往重庆。同年12月28日和次年1月1日,端纳分两次给田伯烈(H.J.Timperley)写了这封长信,详细介绍他随蒋介石视察的所见所闻。  相似文献   

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