Why the Royal Navy sent only two battleships to China

Why did the Royal Navy deploy only two battleships during the Boxer Rebellion?

Two battleships were enough for the heavy naval role; the land campaign needed smaller ships capable of operating in canals and rivers more than additional capital ships.

The Boxer Rebellion occurred before the dreadnought era, so the two ships were contemporary battleships rather than obsolete leftovers. The Royal Navy sent enough heavy force for the political and military requirement. Vessels suited to inland waterways were more useful for the work closer to the fighting.