The decoy ship, although seriously damaged, reached harbour.
On July 10, 1917, a decoy ship, H.M.S._Glen_, a small schooner with auxiliary power and armed with one 12-pounder and one 6-pounder gun, commanded by Sub-Lieutenant K.Morris, R.N.R., was in a position about forty miles south-west of Weymouth when a submarine was sighted on the surface some three miles away.

She closed to within two miles and opened fire on the _Glen_.

The usual practice of abandoning ship was followed, the submarine closing during this operation to within half a mile and remaining at that distance examining the _Glen_ for some time.

After about half an hour she went ahead and submerged, and then passed round the ship at about 200 yards distance, examining her through the periscope, finally coming to the surface about 50 yards off on the port quarter.

Almost immediately she again started to submerge, and fire was at once opened.