A hollow device for shaping a fluid or plastic substance
The Montana sapphires and the matrix have been described by Dr G.
A matrix of wood or iron is covered with successive layers of papers, pasted together so as to form pasteboard.
If the matrix, however, is originally crystalline it does not seem probable that perlitic structure can develop in it.
The matrix consists of n rows and n columns.
When mixed the concrete is carried at once to the position required, and if the matrix is quick-setting Portland cement this operation must not be delayed.