Making and Knowing
A minimal edition of BnF Ms Fr 640 in English Translation

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To distribute the teeth proportionately on their wheels, they do not use a compass because there is no compass so fine that it can draw distances as small as those of the small wheels. But they make a platform (as they call it) out of latten that has been divided into various circles, and each of those circles is divided into equal sections marked by a point. And each circle has a certain number of points, as for example one has 30, another 36, and others 40. Then, on the pierced center of the platform, they place the little wheel. And on the center of the wheel there is a flat line or an alidade which points to the number on the circle that you want to mark on your wheel. Then with a point, they draw a line on the wheel. Then they return the alidade to the following point, and they thus go on marking it the dial. And to mark the points on the circles of their platform, they divide the circle in three and then divide this third part into as many sections as is necessary with regard to the total division of the circle. And, in this manner, they make the teeth’s division and distribution as fine as they please.

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