Artifacts, the products of largely non-verbal processes, can be convincingly interpreted when evaluated by archaeometry -- chemical analysis of materials used in the artifacts, measurement of form and internal structure, surficial markings and physical properties -- as well as the context in which it is found, using backward linkage and forward linkage components. Gordon applies these interpretive tools to an axe head, bloom smelting slag, and to the steam locomotive.
Use of archaeometrical methods allowed the historians to identify the function of Eli Whitney's crucibles through chemical analysis of the slag and to reproduce pattern-welded swords of early medieval Europe by examining the internal structure and finding a method that would allow that structure to be reproduced. An analysis of form inspired Derek Price to suggest that bronze fragments found in a shipwreck could be a complex gear train used to make calendar determinations; using an astrolabe Gerald Forty discovered how and why errors in 16th-century navigation might be made. A check of ductility and strength tests whether or not the artifact could have been used in the function for which it was proposed. Gordon himself used surficial markings to determine the role of artisans in creating interchangeable parts.
Context, however, is needed to support, correct and position the data gathered through archaeometry. For instance, what social structure needed to exist order to produce a particular artifact? The question of backward linkages can be difficult to answer if no supporting documents exist. The Springford Armory, because it has been well documented and has produced many artifacts, has become a standard site of studies in backward linkages. Forward-linkage components are composed of the work or working situations that can be determined from the artifact; for instance, historians who tested a spool lathe found that it would "fully [challenge] the operator's physical and mental abilities." Users and observers are both inherent in the design of an item such as a steam engine in the form of a Greek column; the form contributes nothing to the function, but the makers apparently assumed that observers of this new and frighteningly powerful machine needed the reassurance of a familiar classical form.
The Collins Axe, by its surficial markings, demonstrated the method by which the poll (body) it was to be attached to the bit (blade), and by its metallic composition, the method by which its two parts were made. Forward and backward linkages (The Collins Company was a well-known, well-documented manufactory) suggested that workers were still learning the process of forming axe heads, and that, the axe heads, rather than a representing a reduction in labor, still required considerable skill. An investigation of bloomery smelting suggested something similar: contrary to assumptions that work done during this period was primitive and crude, smelting was a complex, highly skilled effort, requiring expert control of fuel and labor to produce high-quality iron. Finally, Gordon suggests that the continuing fascination with the steam engine train is more than nostalgia: the steam train is an engaging sound-smell-sight experience, and also it is clearly a team effort.
C.f. Robert B. Gordon, "Who Turned the Mechanical Idea into Mechanical