Cinemagazine items: A hospital bed has a “mattress” of sand, and supply of air under pressure to fluidline it, moulding it to the shape of the bocy; let the bath water go and you’ll see the principle of a new machine to separate coal from rock; sometimes a badly broken leg bone will never “knit”, even if the broken sections are held together with a plate; a Birmingham surgeon has designed a frame for a broken leg which seems to heal very severe fractures by affecting the electrical charges in the bone.