According to the book Historical Sites of Warren County, the township was named for Theodorus Jacobus Frelinghuysen, a minister and theologian of the Dutch Reformed Church who came to New Jersey in 1720.
The typical 12' x 24' rectangular (288 sq.ft. of water surface area) concrete pool will cost around $72 per square foot.
A gunite pool does not have a sump line installed in a rock bed like a fiberglass pool should to relieve the hydro-static pressure. A fiberglass pool can float out of the ground if the homeowner does something careless and it is no different with a gunite pool, in each case common sense has to be used.