In science, perfect vacuum refers to a region of space completely devoid of any material particles.
Overview
The quest for the "perfect" vacuum started with the invention of the Magdeburg hemispheres (1657), and was searched for with in the development of the various gunpowder engines (1670s), albeit one difficult to obtain owing to fouling after each explosion, likely due to various amounts of volume taken up by the products the explosion. This fouling problem led French physicist Denis Papin to outline the first theoretical steam engine, i.e. the Papin engine, as detailed in his 1690 "A New Method to Obtain Very Great Motive Powers at Small Cost", wherein he states: [1]
“I at once saw that machines could be constructed, in which water, by the help of a moderate heat, and a little cost, might produce that perfect vacuum which could by no means be obtained by the aid of gunpowder.”