The moulds are opened and closed by cams actuated by compressed air.
When Cuba was the chief sugar-producing country making clayed sugars it was the custom (followed in refineries and found advantageous in general practice) to discharge the strike of crystallized sugar from the vacuum pan into a receiver heated below by steam, and to stir the mass for a certain time, and then distribute it into the moulds in which it was afterwards clayed.
Moulds have been isolated which occasion the formation of citric acid from glucose.
The moulds are made of cast iron.
Their moulds, both for blowing hollow vessels and for pressing ornaments, were as perfect for the purposes for which they were intended as those of the present time.