41. In 2003, boats making more than 13, 000 trips through the waterway carried about 188 million long tons of cargo. 42. Deadweight tonnage was historically expressed in long tons but is now usually given internationally in tonnes ( metric tons ). 43. In the 1939-45 period the Royal Air Force ( RAF ) dropped 15, 696 long tons of bombs on Frankfurt. 44. In 1958 United States shipping magnate Daniel K . Ludwig broke the record of 100, 000 long tons of heavy displacement. 45. General cargo volume declined to 14 . 3 million long tons , which port officials said was in line with national trends. 46. The imperial system uses a stone of 14 lbs, a long hundredweight of 112 lbs and a long ton of 2240 lb. 47. In the period 1939 to 1945 the Royal Air Force dropped a total of 30, 025 long tons of bombs on Duisburg. 48. The Panama Canal was the conduit for 188 million long tons of cargo moved on more than 13, 000 trips in 2003. 49. The axle load is 15 t ( 15 long tons ; 17 short tons ) for which the structures are to be designed. 50. A collier ( cargo ship carrying coal ) may hold 40, 000 long tons of coal and takes several days to unload.
