He was also largely given to the discussion of metaphysical questions, on which his knowledge was simply nil, and a favourite pursuit of his was defining beauty in the abstract, and when he was on this topic the nonsense he talked was something dreadful.

Mengs was a very passionate man, and would sometimes beat his children most cruelly.  More than once I have rescued his poor sons from his furious hands.  He boasted that his father, a bad Bohemian artist, had brought him up with the stick.  Thus, he said, he had become a great painter, and he wished his own children to enjoy the same advantages.

He was deeply offended when he received a letter, of which the address omitted his title of chevalier, and his name, Rafael.  One day I ventured to say that these things were but trifles after all, and that I had taken no offence at his omitting the chevalier on the letters he had written to me, though I was a knight of the same order as himself.  He very wisely made no answer; but his objection to the omission of his baptismal name was a very ridiculous one.  He said he was called Antonio after Antonio Correggio, and Rafael after Rafael da Urbino, and that those who omitted these names, or either of them, implicitly denied his possession of the qualities of both these great painters.

Once I dared to tell him that he had made a mistake in the hand of one of his figures, as the ring finger was shorter than the index.  He replied sharply that it was quite right, and shewed me his hand by way of proof.  I laughed, and shewed him my hand in return, saying that I was certain that my hand was made like that of all the descendants of Adam.

“Then whom do you think that I am descended from?”

“I don’t know, but you are certainly not of the same species as myself.”

“You mean you are not of my species; all well-made hands of men, and women too, are like mine and not like yours.”

“I’ll wager a hundred doubloons that you are in the wrong.”

He got up, threw down brushes and palette, and rang up his servants, saying,—­

“We shall see which is right.”

The servants came, and on examination he found that I was right.  For once in his life, he laughed and passed it off as a joke, saying,—­

“I am delighted that I can boast of being unique in one particular, at all events.”

Here I must note another very sensible remark of his.

He had painted a Magdalen, which was really wonderfully beautiful.  For ten days he had said every morning, “The picture will be finished to-night.”  At last I told him that he had made a mistake in saying it would be finished, as he was still working on it.

“No, I have not,” he replied, “ninety-nine connoisseurs out of a hundred would have pronounced it finished long ago, but I want the praise of the hundredth man.  There’s not a picture in the world that can be called finished save in a relative sense; this Magdalen will not be finished till I stop working at it, and then it will be only finished relatively, for if I were to give another day’s work to it it would be more finished still.  Not one of Petrarch’s sonnets is a really finished production; no, nor any other man’s sonnets.  Nothing that the mind of man can conceive is perfect, save it be a mathematical theorem.”