Antonie van Leeuwenhoek, sometimes hailed as 'the Father of Microbiology,' was a Dutch cloth merchant who began his work in obscurity but became the first to develop innovative lens-making techniques for simple microscopes powerful enough to view microbes definitively. Using his simple microscope, which passed light through just one lens, he observed microorganisms as no one had before. His friend, the prominent physician Reinier de Graaf, helped bring attention to his powerful microscopes by writing to the Royal Society of London. From ${}1673$ onward, van Leeuwenhoek regularly submitted letters to the society detailing his observations. In ${}1674$, he described his groundbreaking observations of single-celled organisms. He described these organisms—which we now know were bacteria and protists observed in rain water—as 'animalcules' or 'wee little beasties.' His ${}1674$ report initially produced controversy in the scientific community, but his claims were soon verified when the society sent a delegation to investigate his findings. He subsequently became a celebrated figure, at one point even entertaining a visit by the czar of Russia.