knowledge his obligations to him. I feel it a pleasure, no less than a duty, to celebrate the memory of my predecessor. And what am I more than a forerunner of others yet to be, both in my travels and life?
However, the industry of the count seems to me to have been greater than his knowledge. He appears to have gone to work with a certain reserve, which is altogether opposed to that stern earnestness with which grand objects should be treated.
Nevertheless, his essay in quarto, which is exclusively devoted to the mineralogy of Sicily, has been of great use to me; and, prepared by it, I was able to profit by my visit to the quarries, which formerly, when it was the custom to case the churches and altars with marble and agate, were more busily worked, though even now they are not idle. I purchased from them some specimens of the hard and soft stones; for it is thus that they usually designate the marble and agate, chiefly because a difference of price mainly depends on this difference of quality. But, besides these, they have still another for a material which is the produce of the fire of their kilns. In these after each burning, they find a sort of glassy flux, which in colour varies from the lightest to the darkest, and even blackest blue. These lumps are, like other stones, cut into thin lamina, and then pierced, according to the height of their colour and their purity, and are successfully employed, in the place of lapis lazuh, in the decoration of churches, altars, and sepulchral monuments.
A complete collection, such as I wished, is not to be had at present: it is to be sent after me to Naples. The agates are of the greatest beauty, especially such as are variegated with irregular pieces of yellow or red jasper, and with white, and as it were frozen quartz, which produce the most beautiful effect.
A very accurate imitation of these agates, produced by lake colouring on the back of thin plates of glass, is
