A mechanical means of indirect carving ?reproducing or scaling up a three-dimensional form in correct proportion. A pointing machine is a framework of metal arms which can be fitted around a sculpture to measure the relationship between given points on its surface. A pointing machine permits these measurements to be transferred from a model to another mass of material (usually a block) the block then cut into either by hand or by machine. Pointing machines are especially necessary for the carving of sculptures having complex form which is based on a plastic model. Greek and Roman sculptors are known to have used them. They were re-invented during the Italian Renaissance. Further improvements made during the eighteenth and nineteenth centuries included pantographic devices which allowed small models to be scaled up. The pantograph is a similar device for copying two-dimensional figures.Related link: Stonecarver.com offers photos of an Italian stonecarver using a pointing machine. Also see caliper, full-scale, and piece mold.