History of Hunterdon County tells me a lot of people had 2nd homes in this county were of Philadelphia and surrounding area as well as from New York City for many years. Some commute by old fashioned method - railroad.
772 testators added for Hunterdon County, New Jersey
Currently surnames A-B
Years covered - 1804-1917
It is not only county. There are several states with several counties already online for testators of wills.
Plus other types of probate records, too.
no opt-in and no opt-out, free browsinghttp://www.sampubco.com
W. David Samuelsen