These Plasterings so made, serve to Paint in Fresco upon; for the Colours being laid upon the Mortar before it was dry, pierced it, and Embodied with it; so that the Painting could not be defaced though it were wash'd; which would easily be wash'd off if the Mortar were dry.
They likewise laid these Plasterings upon Partitions of Wood filled with fat Earth, nailing Reeds to them, as we do Laths, and daubing it over with Clay, and then putting on another row of Reeds across upon the former, and another Bed of fat Earth or Clay, upon which they laid Beds of Mortar and Stuck, as we have said before.
For the Plastering of low and moist places, they had a great many other Lib. 7.
Chap. 4. Precautions, especially within the House; for as what belonged to the Out-part of the House, they contented themselves to Plaster from the Bottom of the Wall to the height of three Feet, with Cement.
But as to the Inward-parts of the House, when the Ground without was higher than the lowermost Flooring; they run up a little narrow Wall against the great one, leaving betwixt the two Walls only the distance of a Channel or Sewer, which they made lower than the Flooring, to receive the Water which might be gather'd against the Walls, and let it run out; and to the End they might hinder the gathering of much Water, by the Vapours which might be enclosed between these two Walls, they made towards the top of the little Wall Vents to let it out, and this little Wall was Plastered on the Out-side with Mortar and Stuck, as we have said before.
When the Place was too narrow to permit those Counter-Walls to be made within, they put hollow Tiles one upon another against the Wall, and placed and plaster'd them over with Mortar and Stuck. These Tiles which were Pitch'd over within, and were Demi-Channels, let the Water fall down into the Sewer, which sweat from the great Wall, and so let all the Vapours, which were engendred by Humidity, go out at the Vents.
CHAP. III.
Of the Convenience of Fabricks.