In the 1600s, which scientist discovered microbes in pond water by using a microscope

The first person to discover and accurately describe microbes was the amateur microscopist Antony van Leeuwenhoek (1632 - 1723) of Delft, Holland. He earned his living as a draper and haberdasher but spent much of his spare time constructing simple microscopes composed of double convex glass lenses held between two silver plates. His microscopes could magnify 50 to 300 times and he may have illuminated his liquid specimens by placing them between two pieces of glass and shining light on them at a 45 degree angle to the specimen plane.

From 1673, He sent detailed letters describing his discoveries to the Royal Society of London and it is clear from his descriptions that he saw both protozoa and bacteria.