The New Jersey State Archives has recently placed a series of photographs of the Morris Canal(current bed of the Newark subway) on its website. The pictures date from 1903, when a comission was considering abandoning the canal. Four of them are of Newark: Newark Bay, Broad Street, Plane #12 and Branch Brook Park. They can be acessed at: Park.http://www.state.nj.us/state/darm/links/guides/szmor001images1.html
New Jersey Heritage Magazine has an excellent article on the US Army's Civil War era Ward General Hospital in Newark. Originally located in converted warehouse space on Centre and Market streets, in 1864-1865 the hospital was moved to purpose built buildings in North Newark, near the present day intersection of Garside and 7th Avenue. The article has a neat photo of the hospital at the latter location, which is not quite Roseville, but close. It was pretty rural then.