10. The beginnings of the ruin of cities.
It should be known that when cities are first founded, they have few dwellings and few building materials, such as stones and quicklime, or the things that serve as ornamental coverings for walls, such as tiles, marble, mosaic, jet,100 shells (mother-of-pearl), and glass. Thus, at that time, the buildings are built in Bedouin (style), and the materials used for them are perishable.
Then, the civilization of a city grows and its inhabitants increase in number. Now the materials used for (building) increase, because of the increase in (available) labor and the increased number of craftsmen. (This process goes on) until (the city) reaches the limit in that respect, as was discussed before.
The civilization of the city then recedes, and its inhabitants decrease in number. This entails a decrease in the crafts. As a result, good and solid building and the ornamentation of buildings are no longer practiced. Then, the (available) labor decreases, because of the lack of inhabitants. Materials such as stones, marble, and other things, are now being imported scarcely at all, and (building materials) become unavailable. The materials that are in the existing buildings are reused for building and refinishing. They are transferred from one construction to another, since most of the (large) constructions, castles, and mansions stand empty as the result of the scarcity of civilization (population) and the great decrease in (population) as compared with former times. (The same materials) continue to be used for one castle after another and for one house after another, until most of it is completely used up. People then return to the Bedouin way of building. They use adobe instead of stone and omit all ornamentation. The architecture of the city reverts to that of villages and hamlets. The mark of the desert shows in it. (The city) then gradually decays and falls into complete ruin, if it is thus destined for it.
This is how God proceeds with His creatures.