Page:Victory at Sea - William Sowden Sims and Burton J. Hendrick.djvu/261

1918] friend. Unquestionably the Germans had the same instructions. It would therefore be dangerous for them to attempt to operate in groups, for they would have no way of knowing that their supposed associate was not an Allied or an American submarine. Possibly, even after our submarines had become exceedingly active, the Germans may have attempted to cruise in pairs; one explanation of the strange adventure of the A L-2, as said above, was that there were two U-boats in the neighbourhood; yet the fact remains that there is no well-established case on record in which they did so. This circumstance that they had to operate singly was a strategic point greatly to our advantage, especially, as I shall describe, when we began transporting American troops.