Now that Friedrich's Military Department is got completely into trim again, which he reckons to have been about 1770, his annual Reviews are becoming very famous over Europe; and intelligent Officers of all Countries are eager to be present, and instruct themselves there. The Review is beautiful as a Spectacle; but that is in no sort the intention of it. Rigorous business, as in the strictest of Universities examining for Degrees, would be nearer the definition. Sometimes, when a new manoeuvre or tactical invention of importance is to be tried by experiment, you will find for many miles the environs of Potsdam, which is usually the scene of such experiments, carefully shut in; sentries on every road, no unfriendly eye admitted; the thing done as with closed doors. Nor at any time can you attend without leave asked; though to Foreign Officers, and persons that have really business there, there appears to be liberality enough in granting it. The concourse of military strangers seems to keep increasing every year, till Friedrich's death. [Rodenbeck, iii. IN LOCIS.] French, more and more in quantity, present themselves; multifarious German names; generally a few English too,--Burgoyne (of Saratoga finally), Cornwallis, Duke of York, Marshal Conway,--of which last we have something farther to say at present. In Summer, 1774, Conway--the Marshal Conway, of whom Walpole is continually talking as of a considerable Soldier and Politician, though he was not in either character considerable, but was Walpole's friend, and an honest modest man--had made up his mind, perhaps partly on domestic grounds (for I have noticed glimpses of a "Lady C." much out of humor), to make a Tour in Germany, and see the Reviews, both Austrian and Prussian, Prussian especially. Two immense LETTERS of his on that subject have come into my hands, [Kindly presented me by Charles Knight, Esq., the well-known Author and Publisher (who possesses a Collection by the same hand): these Two run to fourteen large pages in my Copy!] and elsewhere incidentally there is printed record of the Tour; [In Keith (Sir Robert Murray), _Memoirs and Correspondence,_ ii. 21 et, seq.] unimportant as possible, both Tour and Letters, but capable, if squeezed into compass, of still being read without disadvantage here.