Reconstructing Vernacular Mathematics

Abstract

This article presents an account of my attempt to follow Thomas Hood's instructions for the inscription of two scales on the sector, as laid out in his The Making and Use of the Geometricatl Instrument, Catted a Sector (1598). This will allow us to identify those aspects of the work that he expected readers to infer for themselves. I will then piece together the ways in which readers might have inscribed the scales and build up a picture of the kind of background knowledge that the author expected of his readers. It was this knowledge that made it possible to communicate the tacit skills involved in instrument making through a book. We will find that much ofthe background knowledge required involved experience of manual techniques, rather than abstract principles. Thus, we will develop an understanding of the thoroughly practical nature of vernacular mathematics.