Our first news of damage inflicted on the enemy came in mid-July, soon after the second excursion, though the barrier was then hardly more than begun. The information was authentic but not very circumstantial—the standing policy was against that. Four submarines were mentioned. One of them lost nearly all her fuel and called by wireless for help, so loudly that it was overheard and a British force was sent out to capture or destroy her—but too late. Another German submarine had come to her aid, and the two got safely back. Further details are lacking. The third excursion, together with the British minefields in Area C, completed the equivalent of one system, extending from the Norway coast as far west as 0 degrees longitude. The prohibition against laying any mines farther westward than that was still in force—although the enemy submarines had changed their route so as to pass clear to the westward of the partial barrier. So our fourth excursion began a second “system,” parallel to and five miles distant from the first. Leaving the bases during the night of 28 July, and taking final departure from Buoy No. 2, which marked the north end of the division between Areas A and C, we ran south, clearing the ends of three British deep minefields by three miles—quite safe to do if they were all in their intended places. Then, by an “isodromic” maneuver—not easy and little favored, on account of the precision that is requisite, but necessary on this occasion—our three columns, with _San Francisco_ making a fourth on the left, formed a single line to the right, of eight ships, with two more in an advanced line, all steering about WSW. Being on the outside of the turn, the old _San Francisco_ had to spring from 12 to 16½ knots within a few minutes, to gain her station on the southern flank in time, but no parade ground evolution could have been done more smoothly, and the quickness with which all ships steadied into accurate distance and bearing showed that, in future, the steadying interval could be safely reduced. Originally a half hour, it was cut down to 75 seconds. Commander Moir, a new escort leader, in H.M.S. _Valhalla_, smiled slightly as he read over the mining order for the first time and I asked whether it were about this isodromic movement. He replied, No; he was wondering how they could execute one of the intermediate changes which the order prescribed to be made en route, to sort the ships out from the assembling order to the arrangement which they would be in preparatory to swinging into minelaying formation. It did look mixed at first glance, there was no denying, but I said, “Watch them do it, the Rules of the Road will govern”—and when the time came, I felt quite willing for any one to be a witness. [Illustration: APPROACHING AND LAYING THE FOURTH MINE FIELD. Excursion 4: Formations Before, During, and After Planting.]