As you will be leaving Leipsig pretty soon after you shall have received this letter, I here send you one inclosed to deliver to Mr. Mascow.  It is to thank him for his attention and civility to you, during your stay with him:  and I take it for granted, that you will not fail making him the proper compliments at parting; for the good name that we leave behind at one place often gets before us to another, and is of great use.  As Mr. Mascow is much known and esteemed in the republic of letters, I think it would be of advantage to you, if you got letters of recommendation from him to some of the learned men at Berlin.  Those testimonials give a lustre, which is not to be despised; for the most ignorant are forced to seem, at least, to pay a regard to learning, as the most wicked are to virtue.  Such is their intrinsic worth.

Your friend Duval dined with me the other day, and complained most grievously that he had not heard from you above a year; I bid him abuse you for it himself; and advised him to do it in verse, which, if he was really angry, his indignation would enable him to do.  He accordingly brought me, yesterday, the inclosed reproaches and challenge, which he desired me to transmit to you.  As this is his first essay in English poetry, the inaccuracies in the rhymes and the numbers are very excusable.  He insists, as you will find, upon being answered in verse; which I should imagine that you and Mr. Harte, together, could bring about; as the late Lady Dorchester used to say, that she and Dr. Radcliffe, together, could cure a fever.  This is however sure, that it now rests upon you; and no man can say what methods Duval may take, if you decline his challenge.  I am sensible that you are under some disadvantages in this proffered combat.  Your climate, at this time of the year especially, delights more in the wood fire, than in the poetic fire; and I conceive the Muses, if there are any at Leipsig, to be rather shivering than singing; nay, I question whether Apollo is even known there as god of Verse, or as god of Light:  perhaps a little as god of Physic.  These will be fair excuses, if your performance should fall something short; though I do not apprehend that it will.

While you have been at Leipsig, which is a place of study more than of pleasure or company, you have had all opportunities of pursuing your studies uninterruptedly; and have had, I believe, very few temptations to the contrary.  But the case will be quite different at Berlin, where the splendor and dissipation of a court and the ‘beau monde’, will present themselves to you in gaudy shapes, attractive enough to all young people.  Do not think, now, that like an old fellow, I am going to advise you to reject them, and shut yourself up in your closet:  quite the contrary; I advise you to take your share, and enter into them with spirit and pleasure; but then I advise you, too, to allot your time so prudently, as that learning may keep pace with pleasures; there