"What do you mean by that?" asked Charles.
"Why, we will take particular notice of some great building, or something else that is remarkable where we come out into the street, and by that means we shall be able to find our way back to the hotel."
"Yes," said Charles, "that will be an excellent plan."
So the boys went on, and presently they came out into what seemed to be quite a busy street. It was not very wide, but it was bordered with gay-looking shops on each side. These shops were for the sale of models, specimens of marbles, Etruscan vases, mosaics, cameos, and other such things which are sold to visitors in Rome. The number of mosaics and cameos was very great. They were displayed in little show cases, placed outside the shops, under the windows and before the doors, so that people could examine them as they walked along.
"O, what a quantity of mosaics and cameos!" exclaimed Rollo.
"What are mosaics and cameos?" asked Charles.
As perhaps some of the readers of this book may not know precisely the meaning of these words, I will here explain to them, as Rollo did to Charles, how mosaics and cameos are made.
In the first place, in respect to cameos. Imagine a small flat piece of stone, of different colors on the two sides, say white and black. We will suppose that the white extends half through the thickness of the stone, and that the remaining part of the thickness is black. Stones are often found with such a division of colors, not only white and black, but of all other hues.
Now, the artist takes such a stone as this, and marks out some design upon one side of it, say upon the white side. Perhaps the design may be the figure of a man. Then he cuts away all the white of the stone except the figure; and the result is, that he has the figure of the man, or whatever else his design may be, in white, on a black ground, and the whole in one piece of stone, all solid.
Besides stone, shell is often used for cameos; many shells being pink, or of some other such color on the inside, and white towards the outside. In such a case, the figures of the design would be pink, or whatever else the color of the stone might be, on a white ground.