I'm looking at a chart of world population from 10,000 BCE to modern times. It appears the world population rate rose sharply somewhere around the 1700's (and maybe a tad bit earlier):

I'm confused because it is earlier then expected (as I understand things). First, efficient fertilizer production did not occur until the early 1900s, so food production was mostly constant (confer, Haber process). Second, preventative and curative medicine is rather modern and seems to be dated somewhere after the 1800's, and penicillin debuted the early 1900's (confer, History of medicine).
What caused the increase in world population rate around 1700's?