The Rebel Army Of The Potomac--gen. Beauregard

MaiKissas Junction, July 7. This place still continúes the head quartera of the iirmy of the Potomac. Th ere are many indioations of un intended forward movoment, the botter lo invite the eneniy to an engagement, but the work of fortifieation still continúes. By nature, thu position is one of the ströngest that could have been found in the whole State. Abmit hall way beUeen the easteni spur of the Blue Ridge and the Potomac, below Alexandria, it comnwnds the whole uountrv between so perfeetly thero is scarcfify a possibility tl ita being turned. The ri'ght wing stretches off tow ard the headwaters of the Occoquan, through a wooded country, whioh is üiisilv made impassaulo by tho telling of trees. The left is ■ ruiling table land, easily commanded by the snecessive elevatione, till you reach a country rough and so ruggod that it is a defense itself. The key to tho vvholo position, in fact, is procisely that point wbich Gen. Beauregard choee for his center, ar.d which he lias fortifiod so atrongly that, in the opinión of military men, 5000 men could thero hold 20,000 at bay. The position, in fact, is fortiüed, in part, bv, nature herself. It is a succession of hills, nearly equal distance Irom eaeh other, in front of which is a ravirie so deep and so thickly tvooded that it is impassable, only at two points, and those through gorgee which filty men can defend against a whole anny It was at one of these points that the Washington Artillery was at tirst encamped, and though only halt the batlalhon was then there Md wü had only one company of ïiifantry to support us, we slept as sounilly under the proteqtion of our guns as if we had been in a fort of amplest dimensions. Of the furtificiiiions superadded here by Gen. Beauregard to those of nature it is not proper to peak Tho general reader, in fuct. will have a sufticently preciso idea of them by conceiving á line of forts souie tvvó miles in extent, zig-zag in form, with angles, saiients, bastions, casmnates, and every thiiig that properly bolongs to worka of vliis kind. Tho strength and advantage of this position at Manassas aro very rnuch ;ncreased by the fact that fourtoen miles further on is a position oí similar formation, while the country botween is ftdiüirably adaj)ted to the nubsistence and nlrenchment of troops in nuinb ers as large as they can ea ily be mancEuvured on the real buttle finid Water is good and ubuudant ; forage .-neb as is every w here found in ilie rich farming districts of Virginia, and the communication from all parta of the country easy. Here, overlooking an extensivo plain, watered by mountain Btreauii which uhimately find their way to the Potomac, and divided into verdunt tields of wheat, ai:d oats, an 1 corn, pasture a'id ineadow, are the headquarleis of the advanced force of the armv f the Potoiriue. They are Soulh Carolinians, Louisianiann, Alab.anians, ALissisr-ippians and Virginians f r the most part; the first two smgularly enoug-h, being in front, and that they will keep it thvir triends a! home inay rest assured. Never havo I seen a tiner bodv of men - men who were more obedient to discipline or breathed a more self-sacriticing patiiotism. As might l)e expecled irom the skül with which ha lias chosen hift position, ar.d the system with which he encarnps nd moves, his men, Gen. Bea.iregard is very popular here. I doubt if Napoleon had more the uudivided confidunce of his army. By nature, as also by u wise policy, he is very reticent. Not an individual here knowa his plans or a single move of a regiment bofore it is muda, umi theo only the Colonel and his mea know whore it is to gu. There is not a man horu whu can give uny thing üke u satisfactory answer how many men he has or where his exact lines are. For the distance of tourteen miles around you soa tent avurywheru, and from them yon can make a rough es imate of his men, but how many moro are encamped on the by-roads and n ihe iorests none cao teil. Thu uew corner, Irom what he sees atfiïst glance, puts down the miinber at 80,000 ; those who have been here longest estímate his force at 40,000 or 50,000, and some even at 60,000 strong. And thero is the same discropanoy as to the quant.ity oi hia artillery. So close does the General keep his aü'airs to kimself, his left hand hurdly knovvs what his right hand doeth, und 6o jealons is he of his prerogati ve of a commanding officer that I verily believe if he euspected his coat of any acquaintance with the plans revolving within him, he would cabt it from him. The (ieneral's headquartors ia u little (arm house, about fifte9n feet by twenty, frnnting on one of the roads luading to Alfxandria. The ground floor is divided into two rooms The front ono is ñlled with desks atwliich clerks git writing, or engaged in business of a vaned clmrncter. The back I one appears to bo uned for a Btoruroom ! and kitchen. Abova, the san. e división continue, and the front room is the General's aprtment It is about fif teen lcet long by ton nide, ind hnng witli loops oí' tho State and country aruuod. In the centre is ii plain pino taulo, on whieh lie, neatly frtlded up, wliat the visitor would naturally take lo be plans, specifiiiations, surceys, geomotrical drnwingB, &c , and by their side military posts. Everything has the air of neatneaa, oooThess and mathematical cnksultttion Of oourpe there is notliing ín the room bnt wh:it pertains to the office, and to most eyes it wonld uppear somewhat bare, but what there is, is arranged with so much taste that tl. e general impression is by no raeacs unpleasing. The General is in his room tho greater part of ihe duy, apparently occupiod with bis plana and report. Then hour after hour he siís alone by his neat littlo pine table, maps, plans and specification! before hiin, and large open uindows open behind and aronnd hi in, at first sight the jold, oaleulating, unsympathising mathematician. Every now and then an t.id enters with a report or a uies.-age. which is delivered ín a military Ptyle, deliberately examined in silocce, tho corresponding order promply written out or delivered in as few worde as possible, and our mathematical iceberg is alono aguin. When a visitor drops in, however, at a leisure moment, the formality of the officer readily gives way to the interchange of civilities which clia'acterize our poople at Lome, but nothing more. Even at the table, when the General M daily surrounded by the most distingmshed gentlemen of'tho country, there appeara to bo a distance which all suppose is natural to his posuion,but which is ftiroly iound eleewhere, The leading characteriatie of Gen. Beauregard'a mind i.s cloaress of percaption. Superadded lo this is a strictly inathematical education. Thi you see in every word and look, even ín the expression pi his face. Sities, costeña and tángents stick out evoiywhere. In person he is ftlender, but is compactly built and extreir.ciy neat. Add to this a precisión of marmer, .slighily moditiüd by the ease which charaoteridüí the well brcd mau of the vvorïd, and you havo a oorreot iden of the man whose word is law and gospel throughout one of the largest, and most intelligent and best appointed armies ever assembled on the American Continent. In his personal staS the General has been peculiarly fortúnate. They are principally trom South Carolina, the saine he had with hiin at the siege of Fort Sumpter, all f ihem ' ed, discreet gentlemen, of the most pleasing manners. Among them I have been happy to meet Ooi. Preston, so long a resident and sx v known in Louisiana, whose genial BOisiety must be a happy relict to the severa tabura oí the (tv. The genoral's mess is very much in keeping with his character, and simple enuugh for Napoleon himsclf. It is servecl on a long pine table, set in an pen piazza of the farmhouse, and all iis friends are hospitably welcotnod to it thiee limes a day. The General s;ts nearly in the middle, his aids imine diately on one side, and his latest guests on the other; the rest of the company as they may chooseor chance to seat themsttlvea. The vianda are such as the country ..round aflords ; onlv the rice was " imported," and ith it, I suspect, a South Carolinaian cook, tor every kernel was as independent as the State from which it came. II. V