A simultaneous advance towards the Canal was made, on the left of Aubervilliers, by the 3rd Battalion of the 1st Pomeranian Landwehr, and the 10th Regiment of Hussars; which maintained the communication with the First Corps. A sharp tiraillade took place, which terminated in the withdrawal of these troops to their former position.
By means of this reconnaissance it was made sufficiently manifest that the line of the Canal of St Denis could not be carried without a serious assault, preluded by a heavy cannonade. It then became a question with the Allied Commanders, who had thus, most fortunately, the opportunity of concerting measures in person, Whether it would not be advisable to endeavour to turn the Enemy's strongly fortified lines of St Denis and Montmartre, by masking those lines with one Army, whilst the other should move off to the right, and cross to the left bank of the Seine, lower down the stream.
Although this movement would have the effect of extending and dividing the Allied forces, and consequently of augmenting the chances of success on the part of the Enemy: should the latter possess the disposition and the means, not only of acting determinedly on the defensive, but also of assuming the offensive, accordingly as circumstances might favour the attempt; still any defeat of this kind was fully counterbalanced by the advantages which the plan presented. It cut off the entire communication with Normandy, from which Paris derived its chief supplies; whilst the approach of the Bavarian Army towards the opposite side was gradually limiting the resources of the capital in that quarter. It enabled the Commanders to present their forces simultaneously at different points: and thus, by continuing that display of vigour which had characterised their advance, they were far more likely to impose upon the morale of both the defeated Army and the citizens, than by limiting their combined operations to the attack of the stronghold presented by the lines of St Denis; for to do this, would, in all probability, require time, and it was evident from the repeated Proposals made by the French Government for a Suspension of Hostilities, that time was their great object, whether for the purpose of facilitating the collection and organisation of their resources, or in the hope of obtaining more favourable terms from the Allies.
It had also been tolerably well ascertained that, although fortified works had been thrown up on the right bank of the Seine, the defence of the left bank had been comparatively neglected. A further inducement towards the adoption of this plan arose from a Report which was now received from Major Colomb, stating that although he had found the Bridge of Chatou, leading to Malmaison, destroyed: he had hastened to that of St Germain, on hearing that it had not been injured; and succeeded in gaining possession of it at the very moment the French were on the point of effecting its destruction. The Bridge of Maisons, still lower down the stream, was also taken and occupied.
No time was lost by the Prussian Commander in taking advantage of the captured Bridges across the Seine.
Lieutenant Colonel Sohr received an Order that night to move, with his Cavalry Brigade (the Brandenburg and Pomeranian Hussars), from the vicinity of Louvres, and to regulate his march so that he might cross the Seine at St Germain on the following morning. Thence he was to proceed so as to appear, with his Brigade, on the 1st of July, upon the Orleans road from Paris; where he was to interrupt this communication, and increase the confusion already produced in that quarter by the fugitives from the capital. Altogether, he was to act independently and discretionally; and, as far as practicable, to impede the supplies of provisions from the Western and Southern Provinces.
It was arranged that the Prussian Army should move to its right for the purpose of crossing the Seine; and, in order to mask the operation as much as possible, the Advanced Posts of the First and Fourth Corps d'Armée were to remain in their present position until the arrival of the Anglo-Allied Army, which was expected to take place on the evening of the 30th.
The Third Corps was directed to resume, at five o'clock in the morning of the 30th, its march upon Gonesse; and thence to proceed to St Germain: but in such a manner as to conceal its movements by means of the valley of Montmorency, and not to reach the more open ground about Argenteuil until darkness should have completely set in. From the latter point it would then complete its march to St Germain.
The First Corps was ordered to break up from its bivouac at ten o'clock in the evening, and march southward of Gonesse by Montmorency, Franconville, Cormeilles, and Maisons, at which latter point it was to cross the Seine, and immediately open a communication with the Third Corps.
The Fourth Corps d'Armée was directed to move, at daybreak of the 1st of July, by the right of St Denis, and to bombard this place during its march to Argenteuil; in which direction it was to effect a junction with the First and Third Corps. The Advanced Posts of the First and Fourth Corps were to remain until relieved by the British troops; and then, in like manner, to follow the rest of the Army.