Louis Pasteur 's 1859 experiment is widely seen as having settled the question of spontaneous generation. He boiled a meat broth in a flask that had a long neck that curved downward, like that of a goose or swan. The idea was that the bend in the neck prevented falling particles from reaching the broth, while still allowing the free flow of air. The flask remained free of growth for an extended period. When the flask was turned so that particles could fall down the bends, the broth quickly became clouded. However, minority objections were persistent and not always unreasonable, given that the experimental difficulties were far more challenging than the popular accounts suggest. The investigations of John Tyndall, a correspondent of Pasteur and a great admirer of Pasteur 's work, were decisive in disproving spontaneous generation with dealing with lingering issues. Still, even Tyndall encountered difficulties in dealing with the effects of microbial spores, which were not well understood in his day. Like Pasteur, he boiled his cultures to sterilize them, and some types of bacterial spores can survive boiling. The autoclave, which eventually came into universal application in medical practice and microbiology to sterilise equipment, was not an instrument that had come into use at the time of Tyndall 's experiments, let alone those of Pasteur.
who is given credit for disproving spontaneous generation
John Tyndall