‘Their cavalry. Once they reach the head of the column I should imagine they will attempt to get round Wilson’s left flank. If that happens, then his brigade will be forced to form square. That’s when their infantry will advance. This could turn to the enemy’s advantage, unless something is done.’ He tugged his reins and walked his mount over to the rocket battery’s commander.

‘Hughes, isn’t it?’

‘Yes, sir.’

‘Your rockets can fire up to two miles, I believe.’

‘That’s right, sir. Of course they will not be accurate at such a range.’

‘They are not accurate at any range,’ Arthur replied tersely. ‘So we should be thankful the enemy are providing us with such a large target. Now then, you see the enemy’s cavalry?’

Lieutenant Hughes glanced to the east and nodded.

‘Then aim for them, if you please. Let us see what your contraptions can achieve.’

The officer grinned and touched the brim of his hat before turning away to order his men to align their launch troughs towards the distant target. When all was ready he gave the order for the first rocket to be launched. The sergeant gave his firing cord a sharp tug, the flintlock snapped shut with a spark and the short fuse sputtered for a few seconds before the charge was ignited. With a harsh, hissing roar the rocket leaped from its trough with a brilliant jet of fire and cloud of smoke. Arthur watched the spiralling path of the rocket as it rose to the top of its arc and then curved down towards the French column. It exploded with a flash and white puff some distance above the enemy. Arthur saw several of the soldiers struck down by shrapnel, while others ducked, forcing the column to stop.

‘Very good!’ Arthur grinned at Hughes. ‘That’s put the wind up them. Kindly continue your good work.’

‘With pleasure, sir.’

The second rocket went wildly astray, over the river where it slammed into the water close to the boat bridge. Hughes looked sheepish before he turned back to supervise the next rocket. He had better fortune with the following two, which burst on the ground, the first into the infantry column, the second right in the middle of the cavalry regiment, striking down at least a dozen and scattering a hundred more as the horses bolted from the unfamiliar weapon. At the same time the artillery battery had continued to punish the French line which still had not moved, and was standing waiting for the cavalry. A distant boom drew Arthur’s attention to the southern bank of the Adour where more allied batteries were positioned. The range was long but the enfilading fire was soon doing great damage as each shot ploughed into the enemy’s left flank.