I have often wondered about the (seemingly) arbitrary capitalization of words in 17th & 18th century English, and again today, came across this quote by Edmund Burke in Sylvia Nasar's Grand Pursuit (pg. xii):
Edmund Burke, the philosopher, railed at the plight of miners who "scarce ever see the Light of the Sun; they are buried in the Bowels of the Earth; there they work at a severe and dismal Task, without the least Prospect of being delivered from it; they subsist upon the coarsest and worst sort of Fare; they have their Health miserably impaired, and their Lives cut short."
Emphases mine & quoted from Burke's Vindication (pg. 59) according to the secondary source, which Wikipedia tells me was published in 1756.
Are these typographical issues? What are the rules, if any, that governed capitalization of words in texts from this time?