The French had, with much labour and art, constructed a line of fortifications of many miles extent to cover their recently acquired territory in the Spanish Netherlands, and CADOGAN'S HORSE having been selected to form part of the division to be employed in forcing these lines, had an opportunity of distinguishing themselves, and their valour shone forth with as bright a lustre as in any of the heroes in the ancient days of chivalry. The British commander, having by skilful movements succeeded in drawing the main body of the French army from the point selected for the attack, forced the lines at _Helixem_ and _Neer-Hespen_ at day-break on the morning of the 18th of July, and the pioneers levelled a space for the cavalry to pass over; but scarcely had the British horse passed the barriers, when the Marquis d'Allegre appeared with fifty squadrons of cavalry and twenty battalions of infantry to drive back the British forces. The sun had risen, and the French army was in full march to oppose this sudden attack on their lines; hence every moment was of importance, and a sharp fire of musketry having forced the enemy from a hollow way, the Duke of Marlborough ordered forward his heavy cavalry to charge the hostile horsemen. The two squadrons of this regiment led the attack with their characteristic gallantry, and were opposed to adversaries of valour and renown,--the famous Bavarian Horse Grenadier Guards. Against these celebrated antagonists CADOGAN'S HORSE advanced; the weight and power of their compact line were irresistible, and the Bavarians were broken at the first shock; but they soon rallied, and renewing the conflict with increasing ardour, gained a temporary advantage. At this critical juncture the Duke of Marlborough was separated from his troops and in imminent danger, when CADOGAN'S HORSE, exasperated at the momentary repulse, and still more so at the peril of their renowned chief, returned to the charge; the grand spectacle of two spirited corps of heavy cavalry rushing upon each other with reckless fury, was soon followed by the clash of swords and shouts of the combatants as they fought hand to hand with sanguinary fury; but British prowess and British valour soon proved triumphant, and the Bavarians were overpowered and fled before the conquering sabres of CADOGAN'S troopers, who chased their adversaries from the field, took many prisoners, and captured _four standards_. In their flight the hostile horsemen rode over two battalions of their own foot, and these battalions were severely handled by the British horse. Finally, the enemy was routed; the Marquis d'Allegre, and many officers and men were made prisoners, and this gallant enterprise was attended with complete success.