Sometimes scientists need to break down small things into even smaller things. Blood needs to become platelets, plasma, and cells. Cells need to become organelles. Gases need to become isotopes. One of the best ways to achieve this is to put these items into a centrifuge, spin them around at super high speeds, and use the force of that movement to break them up into their individual parts.
The first centrifuge was created by Antonin Prandtl, a German cafe owner. According to a biography written by Prandtl's grand-niece, the design of the device, which he published in a polytechnical journal, was for a machine that worked continuously to separate milk from its fat. There is little known about Antonin or his design, but it likely was created sometime during the mid-1800s (possibly around 1850). Much more is known about Antonin's nephew, Ludwig, an engineer and Nazi sympathizer who would eventually become one of the world's experts on fluid dynamics. Ludwig's father, Antonin's brother, ultimately took most of the credit for the design of the first centrifuge by perfecting the mild-separating system and showing it at the 1875 World Exhibition in Frankfurt.
The next big upgrade to the device, and the one that brought the centrifuge into the laboratory, was invented by Swedish Chemist Theodor Svedberg. In his lab Svedberg was studying colloids -- a substance, which, in the simplest possible terms, is made up of matter in one type of state evenly dispersed within matter that is in another type of state. (Whipped cream, for example, is a colloid of gas and liquid.) Svedberg wanted to better understand the (much more complex than whipped cream) colloids he was studying and so he created a device that would separate the colloids out into their individual parts.