General Meade broke up his quarters at Taneytown, as he states, at eleven P. M. on Wednesday, and reached Gettysburgh at one A. M. Thursday, July second. Early in the morning he set to work examining the position of the various army corps. It is hardly true to say that he imitated the example of all prudent commanders on the eve of a battle, and made a complete survey of the ground he occupied.

It was on these occasions that the genius of the First Napoleon revealed itself; for at a glance he saw the advantages of his own position and the assailable point of the enemy. It seems that General Lee was somewhat more astute than Meade in this; for in his report he states what he deemed the most favorable point for his attack. In front of General Longstreet, (opposite our left wing,) Lee remarks, the enemy held a position from which, if he could be driven, it was thought our army could be used to advantage in assailing the more elevated ground beyond, and thus enable us to reach the crest of the ridge. That officer, then, was directed to carry this position. It is plain enough that Lee regarded the point where our left was posted as the key to our position, and if that could be taken from us our defeat was inevitable. It is not to be supposed that General Meade refused to see this; but as he makes no mention of it in his report, I propose, for the sake of the future historian of the battle, to tell what I know about it.

Near this important ground was posted the valiant Third corps, and its commander, General Sickles, saw at once how necessary it was to occupy the elevated ground in his front toward the Emmettsburgh road, and to extend his lines to the commanding eminence known as the Roundtop, or Sugarloaf Hill. Unless this were done, the left and rear of our army would be in the greatest danger. Sickles concluded that no time was to be lost, as he observed the enemy massing large bodies of troops on their right, (our left.) Receiving no orders, and filled with anxiety, he reported in person to General Meade and urged the advance he deemed so essential. Oh! said Meade, generals are all apt to look for the attack to be made where they are. Whether this was a jest or a sneer Sickles did not stop to consider, but begged Meade to go over the ground with him instantly; but the Commander-in-Chief declined this on account of other duties. Yielding, however, to the prolonged solicitations of Sickles, General Meade desired General Hunt, Chief of Artillery, to accompany Sickles and report the result of their reconnaissance. Hunt concurred with Sickles as to the line to be occupied — the advance line from the left of the Second corps to the Roundtop Hill — but he declined to give any orders until he had reported to General Meade, remarking, however, that he (General Sickles) would doubtless receive orders immediately.

Two P. M. came, and yet no orders. Why was this? Other orders than those expected by General Sickles were, it appears, in preparation at headquarters. It has since been stated, upon unquestionable authority, that General Meade had decided upon a retreat, and that an order to withdraw from the position held by our army was penned by his Chief of Staff, General Butterfield, though happily its promulgation never took place. This order is probably on record in the Adjutant-General's office.

Meanwhile the enemy's columns were moving rapidly around to our left and rear. These facts were again reported to headquarters, but brought no response. Buford's cavalry had been massed on the left, covering that flank with outposts, and videttes were thrown forward on the Emmetsburgh Road. While awaiting the expected orders, Sickles made good use of his time in levelling all the fences and stone walls, so as to facilitate the movements of his troops and to favor the operations of the cavalry. What, then, was the surprise of Sickles to see of a sudden all the cavalry withdrawn, leaving his flank entirely exposed! He sent an earnest remonstrance to General Meade, whose reply was that he did not intend to withdraw the cavalry, and that a part of this division (Buford's) should be sent back. It never returned. Under these circumstances, Sickles threw forward three regiments of light troops as skirmishers and for outpost duty. The critical moment had now arrived. The enemy's movements indicated their purpose to seize the Roundtop Hill; and this in their possession, General Longstreet would have had easy work in cutting up our left wing. To prevent this disaster, Sickles waited no longer for orders from General Meade, but directed General Hobart Ward's brigade and Smith's battery (Fourth New-York) to secure that vital position, and at the same time advancing his line of battle about three hundred yards, so as to hold the crest in his front, he extended his left to support Ward and cover the threatened rear of the army.

These dispositions were made in the very face of the enemy, who were advancing in columns of attack, and Sickles dreaded lest the conflict should open before his dispositions were completed. At this juncture he was summoned to report in person at headquarters to attend a council of corps commanders. His preparations were of such moment and the attack so near that General Sickles delayed attending the council, while giving all his attention to the carrying out of his orders. A second peremptory summons came from General Meade, and, leaving his unfinished task to the active supervision of General Birney and General Humphreys, Sickles rode off to the rear to headquarters. Before he had reached there, the sound of cannon announced that the battle had begun. Hastening rapidly on, he was met by General Meade at the door of his quarters, who said: General, I will not ask you to dismount; the enemy are engaging your front; the council is over. It was an unfortunate moment, as it proved, for a council of war. Sickles, putting spurs to his horse, flew back to his commad, and, finding that Graham's brigade was not advanced as far as he desired, he was pushing that brigade and a battery forward about a hundred yards, when General Meade at length arrived on the field. The following colloquy ensued, which I gathered from several officers present: Are you not too much extended, General? said Meade. Can you hold this front? Yes, replied Sickles, until more troops are brought up; the enemy are attacking in force, and I shall need support. General Meade then let drop some remark, showing that his mind was still wavering as to the extent of ground covered by the Third corps. Sickles replied: General, I have received no orders. I have made these dispositions to the best of my judgment. Of course I shall be happy to modify them according to your views. No, said Meade, I will send you the Fifth corps, and you may send for support from the Second corps. I shall need more artillery, added Sickles. Send for all you want, replied Meade, to the artillery reserve. I will direct General Hunt to send you all you ask for. The conference was then abruptly terminated by a heavy shower of shells, probably directed at the group, and General Meade rode off. Sickles received no further orders that day. There is no doubt, I may venture to add, that Sickles's line was too much extended for the number of troops under his command; but his great aim was to prevent the enemy getting between his flank and the Roundtop alluded to. This was worth the risk, in his opinion, of momentarily weakening his lines. The contest now going on was of the most fierce and sanguinary description. The entire right wing of the enemy was concentrated on the devoted Third corps; for the object of Lee, as he states, was to carry the ground which Sickles occupied, and which both generals evidently regarded as of the highest importance. While this terrific combat was raging on our left, Lee ordered Ewell to attack our right wing, and Hill to threaten our centre, both with the object, as he says in his report, to divert reenforcements from reaching our left, which, as we have seen, Longstreet was directed to carry. Well may General Meade, in his report, say, The Third corps sustained the shock most heroically; for they fought like lions, against tremendous odds, for nearly an hour before the Fifth corps came up under Sykes, who was immediately put in position by General Sickles to the left of the Third corps, and General Sykes was desired to relieve Ward's brigade and Smith's battery on the Roundtop, and hold the line from thence to Birney's left, (First division, Third corps.) Strange to say, this movement was not promptly carried out, and there was imminent danger of losing the Roundtop, for Longstreet was making desperate exertions to carry it. Fearing this result, Sickles sent orders to General Crawford, of the Fifth corps, to reenforce Ward's brigade, but he declined to move without orders from his own corps commander, Sykes; but Captain Moore, of Sickles's staff, at length overcame his scruples, and he reached the disputed point just in time to prevent its falling into the enemy's hands. Considering our force unequal to the exigency, Sickles called on the heroic troops of the Second corps for support, and they gave it with a will. The struggle now became deadly. The columns of Longstreet charged with reckless fury upon our troops; but they were met with a valor and stern fortitude that defied their utmost efforts. An alarming incident, however, occurred. Barnes's division, of the Fifth corps, suddenly gave way; and Sickles, seeing this, put a battery in position to check the enemy if he broke through this gap on our front, and General Birney was sent to order Barnes back into line. No, he said; impossible. It is too hot. My men cannot stand it. Remonstrance was unavailing, and Sickles despatched his aids to bring up any troops they met to fill this blank. Major Tremaine, of his staff, fell in with General Zook, at the head of his brigade, (Second corps,) and this gallant officer instantly volunteered to take Barnes's place. When they reached the ground, Barnes's disordered troops impeded the advance of the brigade. If you can't get out of the way, cried Zook, lie down and I will march over you. Barnes ordered his men to lie down, and the chivalric Zook and his splendid brigade, under the personal direction of General Birney, did march over them right into the breach. Alas! poor Zook soon fell, mortally wounded, and half of his brigade perished with him. It was about this time — near seven P. M.--that Sickles was struck by a cannon-ball that tore off his right leg, and he was borne from the field.

It was now pretty clear that General Meade had awakened to the fact which he treated with such indifference when pressed on him by Sickles in the morning — that our left was the assailable point, if not the key to our position; for he began to pour in reenforcements whose presence in the beginning of the action would have saved thousands of lives. Perceiving great exertions on the part of the enemy, says Meade's report, the Sixth corps (Sedgwick's) and part of the First corps, (Newton's,) Lockwood's Maryland brigade, together with detachments from the Second corps, were all brought up at different periods, and succeeded, together with the gallant resistance of the Fifth corps, in checking and finally repulsing the assault of the enemy, who retired in confusion and disorder about sunset, and ceased any further efforts. If this remarkable concentration of troops was necessary, at last, to save the left of our army, it is almost incredible that the single corps of General Sickles was able to withstand the impetuous onset of Longstreet's legions for nearly an hour before any succor reached it.

On Friday, July third, the enemy renewed their efforts to carry out the original design of Lee by overthrowing our left wing, and Longstreet was reenforced by Pickett's three brigades, and further supported by one division and two brigades from Hill's corps.

In addition to this heavy mass of infantry, the entire artillery of the rebel army was concentrated against our left. After his oversight of the day before, it may be supposed that General Meade was better prepared to defend his left, and had made adequate preparations. About one P. M. the enemy opened a furious cannonade upon our left and left centre, which continued some two hours, with occasional responses from us. At about three P. M., the enemy moved forward in column, and once more essayed to carry our position on the left. It was during this conflict that General Hancock, commander of the Second corps, a gallant soldier and accomplished officer, was wounded by a musket-ball and obliged to retire. He contributed greatly by his energy and valor to the success of the day. Meanwhile our artillery opened with vigor and inflicted great damage. After a severe and prolonged struggle, the enemy at length fell back and abandoned the contest. Owing to the strength of the enemy's position, says Lee's report, and the reduction of our ammunition, a renewal of the engagement could not be hazarded. Hence it is plain that our good fortune in preserving our position on the left gave us the victory at Gettysburgh; and yet General Meade, not having sufficiently examined the ground before the battle, disregarded the repeated warnings of that sagacious officer, General Sickles, as well as the report of his own Chief of Artillery, General Hunt, who concurred in all the suggestions of the commander of the Third corps. Without meaning to do injustice to General Meade, it must be admitted that his report of this great battle is at such variance with all the statements which have appeared in the press, that it is due not only to history, but to the indomitable prowess of our heroic army, that every fact sustained by concurrent testimony should be given in order to fully establish the truth. I reserve for any suitable occasion abundant documentary evidence to support the facts furnished.

On Saturday, July fourth, both armies continued to face each other during the entire day; without either manifesting a disposition to attack. The enemy says Meade, drew back his left flank, but maintained his position in front of our left, as if always conscious that our vulnerable point was there, and they were loth to retire from it. On the night of the fourth, Lee, finding his ammunition exhausted, and his subsistence imperilled, decided to withdraw, and he began his retreat toward Williamsport, with four thousand of our prisoners, and all his immense trains. On the morning of the fifth, this event became known, and General Meade despatched the Sixth corps in pursuit, together with some squadrons of cavalry. The fifth and sixth of July were employed, says Meade's report, in succoring the wounded and burying the dead. The enemy made good use of all this precious time in pushing on toward Williamsport as rapidly as possible; and it was fortunate for them that detachments were not detailed for these solemn and affecting duties, and that our whole army was not launched in prompt and eager pursuit. They were burdened by heavy trains filled with plunder, without ammunition, and woefully demoralized. Had the half of our army, flushed with success, fallen on them in flank or rear, or anywhere, or any how, General Lee might have got across the Potomac, but his army never. The trains, with the wounded and prisoners, says Lee's report, were compelled to await at Williamsport (about the eighth of July) the subsiding of the river and the construction of boats. . . The enemy had not yet made his appearance. The rebel army must have trembled with anxiety lest the dreaded Yankees should heave in sight before they could escape over the swollen Potomac, which Providence seemed to have destined as the place of their surrender. It was not till the twelfth of July, that our army, too long delayed, came up; but, unfortunately, the enemy had nearly finished their preparations for flight An attack, says Lee, was awaited during that and the succeeding day. This did not take place, though the two armies were in close proximity. Why it did not take place, the country has never yet understood. General Meade, in his report, gives no explanation. The press of the day stated that General Meade again held councils of war at this supreme moment, and that several of his generals opposed falling on the crippled enemy. All we know is that Lee, having completed his preparations, slipped quietly over the river on the morning of the fourteenth. The crossing was not completed until one P. M., says Lee, when the bridge was removed. The enemy offered no serious interruption, and the movement was attended with no loss of materiel except a few disabled wagons and two pieces of artillery, which the horses were unable to drag through the deep mud. It seems that General Meade and the recalcitrant members of the council of war finally made up their minds to attack. But on advancing on the morning of the fourteenth, reports General Meade, it was ascertained he (the enemy) had retired the night previous by the bridge at Falling Waters and the ford at Williamsport.

In striking confirmation of the sketch now given of this important battle, it may be interesting to quote a few brief extracts from the diary of a British officer, who was a guest of General Lee during the campaign in Pennsylvania, and which was published in Blackwood's Magazine, in September last. The writer was an eye-witness of the battle of Gettysburgh, and the hearty praise he lavishes upon the confederate troops and their generals, shows that all his sympathies were with the South, and he takes no pains to conceal his prejudices against the North. Speaking of the moment when the columns of Longstreet had been finally repulsed by our left, on Friday afternoon, July third, he says: It is difficult to exaggerate the critical state of affairs, as they appeared about this time. If the enemy or his general had shown any enterprise, there is no saying what might have happened. General Longstreet talked to me, he narrates, for a long time about the battle. The General said, the mistake Lee had made was in not concentrating the army more and making the attack with thirty thousand men instead of fifteen thousand. It is impossible to avoid seeing, adds the English officer, that the cause of this check to the confederates lies in their utter contempt for the enemy. He continues: Wagons, horses, mules, and cattle, captured in Pennsylvania--the solid advantages of this campaign — have been passing slowly along this road (Fairfield) all day, (July fourth.) So interminable was this train, that it soon became evident that we should not be able to start. As soon as it became dark, we all lay around a big fire, and I heard reports coming in from the different generals that the enemy was retiring, and had been doing so all (lay long. But this, of course, could make no difference to General Lee's plans. Ammunition he must have, as he had failed to capture it from the enemy, according to precedent. Our progress, he continues, was naturally very slow, indeed, and we took eight hours to go as many miles.

I will close these extracts with the following graphic sketch of a stampede which occurred on Monday, July sixth, about seven P. M., and demonstrates most unequivocally the utter demoralization of the confederate army:

About seven P. M.,

It is to be hoped that the above narrative will be regarded as dispassionate, as it is meant to be impartial. Some slight errors may have crept in; but this may possibly stimulate others to come forward with a rectification. Had General Meade been more copious in his report, and less reserved as to his own important acts, the necessity for this communication would not have existed.