The majority of the officers and ratings who pass through H.M.S. Lochinvar are posted to trawlers, which in this war, as in the last, are the mainstay of the Minesweeping Service. These seaworthy little steel ships, with high bows, a length of about 140 feet and a displacement of between 200 and 300 tons, may be seen in scores at any of the mine-sweeping ports of Great Britain, lying three or four abreast alongside the quay, steaming out to their sweeping grounds, or returning to port after their spell at sea.

To-day they are painted grey and carry numbers, but when in harbour they display their names in white letters on a black board. These names are sometimes high-sounding, such as Earl Kitchener, Lady Philomena, Three Kings ; sometimes poetic, such as Sweet Promise, Sea Holly, Waveflower. Some, like Stella Leonis and Stella Rigel, are the names of constellations; some of jewels—Sapphire and Emerald, of trees— Acacia and Olive ; of the Knights of the Round Table—Sir Gareth and Sir Lancelot; or of more mundane gentlemen, such as William Stephens.

Many of them have their own badges, perhaps designed by the Skipper, executed in colour by one of the hands and proudly displayed on the " verandah " which encircles the wheelhouse below the upper bridge. One has a representation of the Old Man of the Sea and a brush ; another a brush, a mine and a flash of lightning (symbol of the magnetic sweep) with the motto Mare clausum vent, which the Skipper will translate for the benefit of new hands as " The sea was closed to commerce before I came." The Stella Rigel has a mine below her starry cluster and the motto (disdaining Latin), " To hell with Hitler."

The trawler's usual armament is a 12-pounder on thewhaleback in thefo'c'sle head, an Oerlikon (or twin -5's) on the gun-platform aft, two Lewis guns on the " verandah " and a Holman projector, which fires shrapnel bombs for short range use against  aircraft.

The normal complement of the mine-sweeping trawler is 23 ; the Skipper and the Second Skipper, who acts as First Lieutenant; the Second Hand, a Chief Petty Officer ; two Enginemen, both Petty Officers ; a signalman (" Bunts "), a telegraphist (" Sparks "), a gunlayer, a wireman (" Torps") ; a motorman, eight seamen, three stokers, a cook,  and an assistant steward.

Every man has his own sweeping station, each seaman his own place at a gun. If the look-out sights an enemy aircraft, surface vessel or submarine, " Action Stations " is sounded by an alarm bell. The Skipper remains on the upper bridge. The Second Skipper is in charge of the 12-pounder. The Second Hand takes the wheel from the helmsman, who closes up to his gun position. One stoker remains below with the engineers. The others serve the 12-pounder ammunition from the magazine and stand by to put out fires on deck. The cook helps to serve the gunlayer, while the wireman fills the pans of the Lewis guns.

When a trawler has brought down an enemy aircraft she is entitled (by the custom of the Service) to paint a swastika on her funnel, while the tally of mines destroyed is kept by chevrons and stars ; a white chevron denotes a single mine, a red chevron five, a blue star twenty-five, and a red star fifty. The record is held by H.M.T. Rolls Royce, wThich to date has a total of over 150 mines to her credit.

The ratings berth for'ard, every man with his own bunk—there are no hammocks. The Skipper's cabin is amidships, below the Chart Room, and there is a tiny Ward Room. All aboard earn their " hard-lying money "—a shilling a day for ratings—although the accommodation is considerably more comfortable than it was in peace time. The food is good and well cooked. The favourite recreations on board are draughts, dominoes, solo and cribbage. There is always a ship's cat, and often a dog as well. In one trawler a budgerigar flies about the mess-deck : another