In the excerpt, what is Hamilton referring to when he describes a "pure, original fountain"?

Alexander Hamilton was one of the Founding Fathers of the United States. He is considered to be one of the promoters of the constitution, as well as the creator of the concept of the nation's financial system. He was also a strong supporter of Federalism. In his famous quote, he refers to the "streams of national power" pouring from the "pure, original fountain". He mentioned this as he was a strong believer that a strong central (federalist) government was the key to the success of the nation.