Group 2--Transports: _Henderson_, _Momus_, _Antilles_, _Lenape_. Escort: _Birmingham_, scout cruiser; _Aphrodite_, converted yacht; _Burrows_, _Fanning_, _Lamson_, destroyers.
Group 3--Transports: _Mallory_, _Finland_, _San Jacinto_. Escort: _Charleston_, cruiser; _Cyclops_, fuel ship; _Allen_, _McCall_, _Preston_, destroyers.
Group 4--Transports: _Montanan_, _Dakotan_, _El Occidente_, _Edward Luckenbach_. Escort: _St. Louis_, cruiser; _Hancock_, cruiser transport; _Shaw_, _Parker_, _Ammen_, _Flusser_, destroyers.
No convoy that ever sailed had a stronger escort or was more closely guarded. Their protection was our supreme duty. Before they left, I cabled Admiral Sims: "I hereby instruct you to furnish escorts, to consist of one division of destroyers for each convoy group from the point of meeting to the point of debarkation."
Submarines were reported operating in the area that had to be crossed. Three of the groups encountered U-boats, Admiral Gleaves reported, and Admiral Sims cabled on June 30th, "First group attacked by submarines, longitude 25 degrees 30, before arriving at first rendezvous; second group attacked longitude 8"; and the next day he cabled: "It is practically certain that enemy knew position of the first rendezvous and accordingly sent a submarine to intercept before juncture with destroyers."
About 10:15 p. m., June 22, the officer of the deck and others on the bridge of the _Seattle_, which was leading the first group, saw a white streak about 50 yards ahead of the ship, crossing from starboard to port. The cruiser was immediately run off 90 degrees to starboard at full speed. The officer of the deck said, "Report to the admiral a torpedo has just crossed our bow." General alarm was sounded, torpedo crews being already at their guns. When Gleaves reached the bridge, the _DeKalb_ and one of the transports astern had opened fire, the former's shell fitted with tracers. Other vessels of the convoy turned to the right and left. The destroyer _Wilkes_ crossed the _Seattle's_ bow at full speed and turned toward the left column in the direction of the firing.
Two torpedoes passed close to the _DeKalb_ from port to starboard, one about 30 yards ahead of the ship and the other under her stern, as the ship was turning to the northward. Captain Gherardi stated that at 10:25 the wake of a torpedo was sighted directly across the _DeKalb's_ bow. A second torpedo wake was reported ten minutes later by the after lookouts.