Those which have been hitherto mentioned, are, nearly all of them, exotic trees, which it is impossible to rear in any other than their native soil, and which are not to be naturalized in strange countries.[1096] It is now for us to speak of the more ordinary kinds, of all of which Italy may be looked upon as more particularly the parent.[1097] Those who are well acquainted with the subject, must only bear in mind that for the present we content ourselves with merely stating the different varieties of these trees, and not the mode of cultivating them, although there is no doubt that the characteristics of a tree depend very considerably upon its cultivation. At this fact I cannot sufficiently express my astonishment, that of some trees all memory has utterly perished, and that the very names of some, of which we find various authors making mention, have wholly disappeared.[1098] And yet who does not readily admit that now, when intercommunications have been opened between all parts of the world, thanks to the majestic sway of the Roman empire, civilization and the arts of life have made a rapid progress, owing to the interchange of commodities and the common enjoyment by all of the blessings of peace, while at the same time a multitude of objects which formerly lay concealed, are now revealed for our indiscriminate use? Still, by Hercules! at the present day there are none to be found who have any acquaintance with much that has been handed down to us by the ancient writers; so much more comprehensive was the diligent research of our forefathers, or else so much more happily employed was their industry. It is a thousand years ago since Hesiod,[1099] at the very dawn, so to say, of literature, first gave precepts for the guidance of the agriculturist, an example which has since been followed by no small number of writers. Hence have originated considerable labours for ourselves, seeing that we have not only to enquire into the discoveries of modern times, but to ascertain as well what was known to the ancients, and this, too, in the very midst of that oblivion which the heedlessness of the present day has so greatly tended to generate. What causes then are we to assign for this lethargy, other than those feelings which we find actuating the public in general throughout all the world? New manners and usages, no doubt, have now come into vogue, and the minds of men are occupied with subjects of a totally different nature; the arts of avarice, in fact, are the only ones that are now cultivated.