sentences:  He was only partially successful however, as the sludge part of the human waste sewage began to build up on mud banks further down stream along the Thames.The seriousness of the problem was highlighted in 1878 when a passenger steamer, The , sank at Gallions Reach following a collision with a cargo vessel, with great loss of life including many children.After the dead were later recovered by watermen, it was found that many had in fact not drowned, but instead had died from ingesting the poisoned waters of the toxic sludge-filled river.