Lisbon, situated near the end of the tongue of land lying between the sea-coast and the Tagus, is defended to the northward by vast mountains, that rising in successive and nearly parallel ranges, end abruptly in a line extending from Torres Vedras to Alhandra on the Tagus. As these ridges can only be passed at certain points by an army, the intersections of the different roads form so many strong positions.
The great mass of the Monte Junto appears to lead perpendicularly on to the centre of the first ridge; but stopping short at a few miles distance, sends a rugged shoot called the Sierra de Barragueda in a slanting direction towards Torres Vedras, from which it is only divided by a deep defile.
From this conformation it results, that an army marching from the Mondego to Lisbon, must either pass behind the Monte Junto, and follow the line of the Tagus, or keeping the western side of that mountain, come upon the position of Torres Vedras.
If sir Arthur Wellesley had adopted the first line of operations, his subsistence must have been drawn by convoys from the Mondego, the enemy’s numerous cavalry would have cut his communications, and in that state he would have had to retreat, or to force the positions of Alhandra, Alverca, and finally the heights of Bellas, a strong position the right flank of which was covered by the creek of Saccavem, and the left flank by the impassable Sierra dos Infiernos. On the other line Torres Vedras was to be carried, and then Mafra or Montechique, following the direction of Junot’s retreat. If Mafra was forced (and neither it nor Montechique could be turned), a line of march, by Cassim and Quelus, upon Lisbon would have been opened to the victors; but that route, besides being longer than the road through Montechique and Loures, would, while it led the English army equally away from the fleet, have entangled it among the fortresses of Ereceira, Sant Antonio, Cascaes, St. Julians, and Belem. Again, supposing the position of Montechique to be stormed, the heights of Bellas offered a third line of defence, and lastly, the citadel and forts of Lisbon itself would have sufficed to cover the passage of the river, and a retreat upon Elvas would have been secure.
Thus it is certain, that difficulties of the most serious nature awaited the English army while acting on a single line of operations; and the double line proposed by sir Arthur was strictly scientific. For if sir John Moore, disembarking at the Mondego, had marched first to Santarem and then to Saccavem, he would have turned the positions of Torres Vedras and Montechique, and then sir Arthur on the other side would have turned the heights of Bellas by the road of Quelus. Junot’s central situation could not in this case have availed him, because the distance between the British corps would be more than a day’s march, and their near approach to Lisbon would have caused an insurrection of the populace. The duke of Abrantes must either have abandoned that capital and fallen vigorously upon sir John Moore, with a view to overwhelm him and gain Almeida or Elvas, or he must have concentrated his forces, and been prepared to cross the Tagus if he lost a battle in front of Lisbon. In the first case, the strength of the country afforded Moore every facility for a successful resistance, and sir Arthur’s corps would have quickly arrived upon the rear of the French. In the second case, Junot would have had to fight superior numbers, with an inveterate populace in his rear, and if, fearing the result of such an encounter he had crossed the Tagus, and pushed for Elvas, sir John Moore’s division could likewise have crossed the river, and harassed the French in their retreat.
2º. The above reasoning being correct, it follows, that to re-embark sir John Moore’s army after it had landed at the Mondego, and to bring it down to Maceira bay, was an error which (no convention intervening) might have proved fatal to the success of the Captain Poulteney Malcolm’s Evidence. Court of Inquiry. campaign. This error was rendered more important by the danger incurred from the passage; for, as the transports were not sea-worthy, the greatest part would have perished had a gale of wind come on from the south-west.
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Explanatory Sketch
of the
CAMPAIGN IN PORTUGAL
in August 1808.
London. Published March 1828, by John Murray, Albermarle Street.
3º. Sir Arthur Wellesley’s project of seizing Mafra by a rapid march on the morning of the 21st, was exceedingly bold; its successful execution would have obliged Junot to make a hurried retreat by Enxara dos Cavalleiros to Montechique, at the risk of being attacked in flank during his march; or if he had moved by the longer route of Ruña and Sobral, it is scarcely to be doubted that the British army would have reached Lisbon before the French. But was it possible so to deceive an enemy inured to warfare, as to gain ten miles in a march of sixteen? was it possible to evade the vigilance of an experienced general, who, being posted only nine miles off, possessed a formidable cavalry, the efforts of which could neither be checked nor interrupted by the small escort of horse in the British camp? was it in fine possible, to avoid a defeat during a flank march along a road crossed and interrupted by a river and several deep gullies, which formed the beds of mountain torrents? These are questions which naturally occur to every military man. The sticklers for a rigid adherence to system would probably decide in the negative. Sir Arthur Wellesley was however, not only prepared to try at the time, but he afterwards deliberately affirmed that, under certain circumstances of ground an operation of that kind would succeed; and to investigate such questions is the best study for an officer.