As a matter of fact the great Leonardo remained infantile in some ways throughout his whole life; it is said that all great men retain something of the infantile. As a grown up he still continued playing, which sometimes made him appear strange and incomprehensible to his contemporaries. When he constructed the most artistic mechanical toys for court festivities and receptions we are dissatisfied thereby because we dislike to see the master waste his power on such petty stuff. He himself did not seem averse to giving his time to such things. Vasari reports that he did similar things even when not urged to it by request: "There (in Rome) he made a doughy mass out of wax, and when it softened he formed thereof very delicate animals filled with air; when he blew into them they flew in the air, and when the air was exhausted they fell to the ground. For a peculiar lizard caught by the wine-grower of Belvedere Leonardo made wings from skin pulled off from other lizards, which he filled with mercury so that they moved and trembled when it walked; he then made for it eyes, a beard and horns, tamed it and put it in a little box and terrified all his friends with it."[72] Such playing often served him as an expression of serious thoughts: "He had often cleaned the intestines of a sheep so well that one could hold them in the hollow of the hand; he brought them into a big room, and attached them to a blacksmith's bellows which he kept in an adjacent room, he then blew them up until they filled up the whole room so that everybody had to crowd into a corner. In this manner he showed how they gradually became transparent and filled up with air, and as they were at first limited to very little space and gradually became more and more extended in the big room, he compared them to a genius."[73] His fables and riddles evince the same playful pleasure in harmless concealment and artistic investment, the riddles were put into the form of prophecies; almost all are rich in ideas and to a remarkable degree devoid of wit. The plays and jumps which Leonardo allowed his phantasy have in some cases quite misled his biographers who misunderstood this part of his nature. In Leonardo's Milanese manuscripts one finds, for example, outlines of letters to the "Diodario of Sorio (Syria), viceroy of the holy Sultan of Babylon," in which Leonardo presents himself as an engineer sent to these regions of the Orient in order to construct some works. In these letters he defends himself against the reproach of laziness, he furnishes geographical descriptions of cities and mountains, and finally discusses a big elementary event which occurred while he was there.[74]