quite as accurate as they were before the firing began, and indeed the exactitude of the results precluded this form of error from explaining the failure to complete the business. At last, when the firing times of the two ships were compared with the observers’ records of the pitching of the shell, the true explanation leapt into sight. The whole show had broken down over the old difficulty of the identification of shots. The people in the aeroplanes could not tell whether a particular shot had been fired by _Mersey_ or _Severn_, and as both ships got the message, neither could tell whose shot had been observed. It followed therefore that the consequent correction was often put on to the wrong gun. Thus, for example, suppose _Mersey_ had fired a shot 300 yards over the target that fell in bush and was invisible to the observers, while _Severn_ had fired one that was 200 yards short and visible. The observers would wireless 200 short, whereupon the _Mersey_ would think that this message was intended for her, and raise her sight by this amount. Her next round, of course, would go still farther into the bush, and suppose this was visible or partially visible to the observer, who might perhaps have missed _Severn’s_ next round, he might telegraph back 500 or 600 over, a correction that _Severn_ might take to herself, and lose her next shot in the bush short of the target. The men on the Rufigi in short discovered for themselves, by their experiences on this first arduous day against the _Koenigsberg_, that the problem of correcting the fire of two separated batteries by the work of a single observer is so exceedingly difficult of solution as to make it hardly worth attempting. The lessons so painfully brought home were put to immediate and most successful use. It was resolved on the second attempt that only one monitor should fire at a time. This was not of course the only experience of value obtained in the first day’s operation for when all the results were collated and compared, a pretty exact knowledge of the actual range from the chosen anchorage to the target was obtained, so that on the second day there were fewer initial rounds lost before shell began to fall in the immediate surroundings of the enemy, where the position of each could be verified. When all ambiguity as to the meaning of corrections was removed, the process of finding the target and keeping the range became exceedingly simple.