Unless you work in a lab, it's possible that you've never seen a pipette in person and only have a vague idea about what it does. But any scientist that has ever worked with liquids will likely say the pipette is one of the most essential tools in the lab. Modern versions of the tool require just a press of a button to pick up a specific volume of liquid and move it. It's a bit like an eyedropper, but with the ability to control specifically how much liquid you are picking up and dispensing. The pipette is most commonly used in genetic research, chemistry, microbiology, and drug development.
In what is probably the most horrifying revelation in all of these lab tool histories so far, the reality about life before formal pipetting is that when scientists didn't have proper tools to move liquids around they just used a straw and their own mouths to create suction. According to a paper titled "Hazards of Mouth Pipetting," produced by the US Army Biological Laboratories in 1966, one of the earliest recorded examples of the hazards of using one's mouth for this purpose came in 1893 when a doctor accidentally sucked a bunch of Typhoid bacteria into his mouth. The paper went on to express concern that it was much too easy to inhale vapors, especially from radioactive solutions, even when the liquid being transferred never made contact with a scientist's mouth.
It's remarkable, given the history of pipettes, that the "mouth pipetting" method managed to continue into the 60s. According to the US Army paper: "the method of avoiding pipetting hazards is so elementary, so simple, and so well-recognized that it seems redundant to mention it." But, nonetheless, the paper goes on to say that only a few institutions at the time had issued rules that forbade scientists from using their mouths to move infectious and toxic materials around their labs. In fact, Manhattan Project scientist Lawrence Bartell accidentally ingested plutonium using this method -- luckily he lived to tell the tale.
Scientists certainly had the tools available to them at that time. The earliest pipettes were invented by Louis Pasteur, one of the scientists responsible for proving the validity of germ theory. For a few hundred years before Pasteur came around science had suspected the existence of microorganisms, but had never been able to prove their existence. Pasteur managed to show that microbes were responsible for food going bad by closely studying the fermentation of milk and wine. The result of this research was twofold. First, of course, was his most famous achievement: developing the method of pasteurization, which uses heat to remove bacteria from food. The second was the creation of rudimentary pipettes, know today as the Pasteur Pipette, which he deemed essential to prevent liquids from becoming contaminated when they were moved from place to place in his lab. The new method used thin glass tubes with a rubber bulb at the end, which created suction. Pasteur Pipettes don't have the measuring sophistication that modern pipettes have, but they are still in use today (now also called "transfer pipettes" they're usually made of one single piece of plastic).