there was reasonable hope of the enemy risking a decision this
consideration tended to override all others; but when, as in Nelson's case
in the Mediterranean, the hope was small, the exercise of control tended to
take the paramount place.

The second complexity arose from the fact that however strong might be our
battleship cover, it is impossible for it absolutely to secure cruiser
control from disturbance by sporadic attack. Isolated heavy ships, taking
advantage of the chances of the sea, could elude even the strictest
blockade, and one such ship, if she succeeded in getting upon a line of
communication, might paralyse the operations of a number of weaker units.
They must either run or concentrate, and in either case the control was
broken. If it were a squadron of heavy ships that caused the disturbance,
the practice was to detach against it a division of the covering
battle-fleet. But it was obviously highly inconvenient and contrary to the
whole idea on which the constitution of the fleet was based to allow every
slight danger to cruiser control to loosen the cohesion of the main fleet.

It was necessary, then, to give cruiser lines some power of resistance.
This necessity once admitted, there seemed no point at which you could stop
increasing the fighting power of your cruisers, and sooner or later, unless
some means of checking the process were found, the distinction between
cruisers and battleships would practically disappear. Such a means was
found in what may be called the "Intermediate" ship. Frigates did indeed
continue to increase in size and fighting power throughout the remainder of
the sailing era, but it was not only in this manner that the power of
resistance was gained. The evil results of the movement were checked by the
introduction of a supporting ship, midway between frigates and true
ships-of-the-line. Sometimes classed as a battleship, and taking her place
in the line, the 50-gun ship came to be essentially a type for stiffening