Thursday 9 April 2020

plaster of paris

Our faithful antiquarian and bibliophile, JF Ptak Science Books, is always uncovering interesting historical passages and ephemera and lately directs us to an 1834 invention by M. Richard Rettford to take casts mechanically by recording the impression of the object to be modelled by the indent on a matrix of tiny needles through a mesh. Though we all might be familiar with the pin art screens that are the domain of executive toys, back in the nineteenth century proposing such a solution as this physiognotype for non-intrusive three-dimensional sampling and replication was a really innovative idea.