48 General View of the Certosa and Convent ofPavia. [Plates 29 to 33.
struction ; secrets of solidity in building; rules for the preparation and the use
of material; mastery of the divers properties of stones, of clays, of lime, of
plaster, of timber, &c. In fact, in the structures of those times, the ground-
plan of the building, the arrangement of supporting piers, the skilfully masked
buttresses helping to resist the thrust of the arch, the bulge of walls, convey
valuable lessons. It is very exceptional for cornices or decorations formed of
terra-cotta or of bricks, to be found even at this day broken or displaced by
General Vieiv of the Church of the Certosa, Pavia.
any degree of exposure to the elements ; so that, as we have already observed
in speaking of the tower of San Gottardo, this material has defied and still defies
frost, damp, dog-days, and, in one word, all sorts of bad weather. The injuries
sometimes suffered by such structures are traceable either to original inexact-
ness in fitting piece to piece, or to violent shocks which they have undergone, or
to the slow unceasing growth of weeds which, taking root in seams and chinks,
exerted a wedge-like power. Generally speaking the mortar used to unite
stones and bricks was so well mixed, and composed of such just proportions and
struction ; secrets of solidity in building; rules for the preparation and the use
of material; mastery of the divers properties of stones, of clays, of lime, of
plaster, of timber, &c. In fact, in the structures of those times, the ground-
plan of the building, the arrangement of supporting piers, the skilfully masked
buttresses helping to resist the thrust of the arch, the bulge of walls, convey
valuable lessons. It is very exceptional for cornices or decorations formed of
terra-cotta or of bricks, to be found even at this day broken or displaced by
General Vieiv of the Church of the Certosa, Pavia.
any degree of exposure to the elements ; so that, as we have already observed
in speaking of the tower of San Gottardo, this material has defied and still defies
frost, damp, dog-days, and, in one word, all sorts of bad weather. The injuries
sometimes suffered by such structures are traceable either to original inexact-
ness in fitting piece to piece, or to violent shocks which they have undergone, or
to the slow unceasing growth of weeds which, taking root in seams and chinks,
exerted a wedge-like power. Generally speaking the mortar used to unite
stones and bricks was so well mixed, and composed of such just proportions and