082r - - - - - Heat of copper
It is hot enough when you see it neat & even on top, without filth.
Box mold
Iron & copper make it porous if the metal touches it, & the wood warps. Thus, make a mold of wood, & have box molds of bricks made inside this mold of whatever thickness that you want.
Glair of eggs
Glair of eggs gives strength to sand to make several casts.
Watchmakers
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, & 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, 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, & 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 & then divide this third part into as many sections as is necessary with regard to the total division of the circle. &, in this manner, they make the teeth’s division & distribution as fine as they please.
Figure
