Mcclellan Moves His Army

New York, Aug. 1!) A Tribune letter says: Iliifiison'sj evacuatou without t I iflc, withoUt (t blIW, Without OVO!) ti:'.: loss of ri:nO. 'í he immense ariny of the l'otom-io, oüi-ers and men bag and s, horses, ujinuiition and contrabande re now f ar awav irom HariisonV, Landing, loiving it dcseru-d and desolate. All ngr.ee tbut the whole afluir was admirably esecüted. On Móriday last McCull's divis'.on received ördórs to ttrike ttnte, j.rovido ! t,L daya FatiüQS, and be roaJy to move at a inomenl's no ice. At 9 o'clock at njght the wholo division orrived at tiio uiiarf and örabarkad qirickly on the steairiüi'.s, lui't the Landing Homo timo during tiio nilit tor Aquia Orouk as suppusod, via fe'ortresa Momoe. An order wa8 noxt issued that no inoro Vessela loaded th snppliuswliould proceed fartbörthan Furtrusd Mooroe, ac(l on Wodnestlay lun days' rtions woru h-orvt'd to tho araiy, whioh was required to be in reífdinegí to move at an hout' nutice. On Thureday tho anny cnmmencod evacualing. All the siega 'gnus were removed íiom tho front, and safuly embarked on Thuisday and ycsterdav, on board baiges and si huooere. Portor's coi'ps led tho van of the overland portion of tho army. Ql) Thursday night and Fnday morhing every tent wan structc, and thon, for tho firet time. was it general ly known that the wholo army was about evacoatirvg lfin-ison's Landing. On Thurtiday night h'f'ty sail vosst-ls Ieftthe different wharvu.s loaded with Bfóres, and yeöterday ihe remaindi-r ol the stores were pláóed on bouts anc! 8 teamera by tlie bontrabnii'i.s. All the cavalry that remained before the final departnro of the land forces, acted is piciets, and a strong reur gaard of inl'anti'y and a'rtillery was placed to prottct tho baggage traína. - l'he siök arid ivotihded Wtïo rernaitied at the iüFerent noapttiila woro placed on board tho rfulav Steanboftta belunjiing to the SnhTtary Oominisxion at thu Long Wharf, and wore among the iiist to move out in tho stroam. The erntni!ands weio slipped on pclioonero, bargea and pon toon boats. Gen. McClollan and rnoet oi Kis stül] went by land.