Do you think primary sources or secondary sources are more valuable to modern historians? why?

In italy, the distance between milan in the north and palermo, sicily, in the south is about 550 miles. in the united states, the distance betweenboston, massachusetts, and savannah, georgia, is about 900 miles. do you think the american revolutionaries of 1776 in the 13 colonies faced some of the same challenges as the patriots who struggled for italian unity in the 1860s?  

Dalton developed the first model of the atom that showed the structure of the inside of an atom

Why do people place so much importance on washington, dc?me