When the conflict came to be between the British and the French in the 18th century, battles between equal or approximately equal forces became largely inconclusive. The French, who had fewer ships than the British throughout the century, were anxious to fight at the least possible cost, lest their fleet should be worn out by severe action, leaving Britain with an unreachable numerical superiority. Therefore, they preferred to engage to leeward, a position which left them free to retreat before the wind. They allowed the British fleet to get to windward, and, when it was parallel with them and bore up before the wind to attack, they moved onwards. The attacking fleet had then to advance, not directly before the wind with its ships moving along lines perpendicular to the line attacked, but in slanting or curving lines. The assailants would be thrown into "a bow and quarter line" – with the bow of the second level with the after part of the first and so on from end to end. In the case of a number of ships of various powers of sailing, it was a difficult formation to maintain.