To work a beam trawl successfully, it is necessary to know the character of the sea bottom, whether rough or smooth, and also the time and direction of the tide. The net is trawled with the tide a little faster than it is running, so that sufficient resistance is encountered to keep the net extended. In shooting the trawl, great care must be taken to make it alight on its runners in the correct position for trawling. If the net be twisted, or if it alight upside down, it has been shot “foul,” and has to be hauled up and shot again. In preparing for a shot the net is lowered over the side by adjusting the bridle ropes, and the beam is coaxed into its proper position while the net is still near the surface. The net is then gradually lowered, the boat moving slowly forward. The trawl is generally hauled for the duration of a tide—that is, six hours—during which time it will travel about 15 miles. The net is generally hauled in by a steam capstan, driven by a small donkey engine. When the trawl comes alongside, the beam is secured and the net is gradually hauled over the side by hand until the cod end appears; this is then made fast to a rope and tackle, and hauled above the deck. The cod line is untied and the fish are discharged upon the deck. Since trawling is generally carried out on smooth ground, the greater proportion of the catch consists of certain kinds of demersal fishes that frequent sand and gravel. Of these, the most important are cod, haddock, whiting, ling, hake, catfish, sole, plaice, turbot, and brill. Certain of these species also frequent rocky ground, and are taken in such areas by the line fishermen. Generally speaking, line fishermen work in deeper water than trawlers and capture larger fish, though of fewer species, e.g. cod, halibut, ling, skates and rays. The original sailing trawlers are rapidly being superseded by steam trawlers. The first steam trawling company was formed in 1882. It had a capital of £20,000 and a fleet of four vessels. It trawled on the Dogger Bank for three years with marked success. After this the future of steam trawling was assured. The steam trawler is many times more efficient than a smack, for it can fish in nearly all weathers, including calm, and it can trawl over rough bottoms, owing to its greater power, and can go much further afield. [Illustration: FIG. 15 MODERN STEAM TRAWLER (SECTION) Total length, 160 ft. Length between perpendiculars, 148·5 ft. Greatest breadth (frame), 23 ft. Draught, 13-3/4 ft. _Explanation of Section._—1. Wheelhouse. 2. Captain’s cabin. 3. Collision bulkhead. 4. Crew’s quarters. 5. Store for gear, nets, etc. 6. Chain locker. 7. Fish-pounds (on deck). 8. Fish-hold. 9. Cross bunker (for coal). 10. Main bunker. 11. Passage to bunker. 12. Steam-winch. 13. Stokehold. 14. Lifeboat. 15. Triple expansion engines (650 indicated h.p.). 16. Bathroom. 17. Mate’s quarters. 18. Dining-room and berths for engineers. 19. Storeroom.]