As the Borough grew new schools were constructed to accommodate many more students. Virgin School was the first parochial school built in 1954.The borough borders the Somerset County municipalities of Dunellen and Piscataway Township in Middlesex County; and Bound Brook, Bridgewater Township, Green Brook Township and South Bound Brook in Somerset County.).Males had a median income of ,248 (+/- ,439) versus ,447 (+/- ,086) for females.In 1905, the Lincoln section of Middlesex organized a volunteer fire company and that set the organization of four other fire companies in the Borough.There were already a few schools set up before Middlesex became a borough in 1913.
There were 4,984 households, of which 32.0% had children under the age of 18 living with them, 56.0% were married couples living together, 11.8% had a female householder with no husband present, and 27.1% were non-families.
22.2% of all households were made up of individuals, and 10.8% had someone living alone who was 65 years of age or older.