No. 21952 Colton’s 1855 map showing the sweeping arc of the railroad line in Boston Harbor and its path through the South Bay toward Dorchester. At that time, it was called the Boston and New York Central.
The track for this railroad line leaves Boston and travels to Dorchester, stopping at Newmarket, Uphams Corner, Four Corners/Geneva, Talbot Avenue, Morton Street and Blue Hill Avenue.. It then leads through the western portion of Dorchester toward Mattapan Square. Its stop in Mattapan is a little north of the Square.
The following is from Wikipedia
The line was built as an entrance to Boston for the Norfolk County Railroad and its successors, which originally had to rely on a connection via the Boston and Providence Railroad (B&) from Dedham. The new line, built in 1855, split from the old one at Islington and ran northeast, crossing the Boston and Providence Railroad at Readville. It continued on through Hyde Park and Dorchester before crossing the Old Colony Railroad at South Bay Junction. The line continued into South Boston and made a sweeping curve along a trestle west to downtown Boston and a terminal at Dewey Square.
After several failed reorganizations, the line became part of the new York and New England Railroad (NY&NE) in 1873 and the New England Railroad in 1895. The New England was leased to the New York, New Haven and Hartford Railroad (NYNH&H) in 1898 and became their Midland Division. The line was operationally split at the junction with the Boston and Providence (also leased by the NYNH&H) at Readville, with many trains using the Midland from the southwest switching to the B&P, and some on the B&P from the south switching to the Midland.
In 1874 the Hopkins atlas gives the name New York and New England Railroad.
Colton’s map of Boston in 1855 labels the railroad The Boston & New York Central Railroad.
Walling Map of the City of Boston and Its Envrions (1866) labels the railroad Boston, Hartford & Erie R. R.
The following is from
https://en.wikipedia.org/wiki/New_York_and_New_England_Railroad Southwest from Boston: 1847-1867
At the Boston end, the earliest predecessor was the Norfolk County Railroad, chartered April 24, 1847. The line from the Boston and Providence Railroad‘s branch at Dedham, Massachusetts southwest to Walpole opened on April 23, 1849, and an extension to the Providence and Worcester Railroad in Blackstone opened May 16. The company went bankrupt soon after. The short Medway Branch Railroad was leased in 1851, opening December 29, 1852.
On May 1, 1849 the Southbridge and Blackstone Railroad was incorporated to extend the line west from Blackstone to Southbridge. On its way to Douglas, this railroad passed through Ironstone, where there was a factory that made Kentucky Blue Jeans, and a nearby iron forge. The Midland Railroad was incorporated May 2, 1850 to build a new entrance to Boston, merging with the existing one south of Dedham. The two companies were consolidated with the Norfolk County Railroad on December 12, 1853 to form the Boston and New York Central Railroad, which had the intent of continuing southwest through Connecticut all the way to New York City. The first section of this extension was incorporated in May 1853 as the East Thompson Railroad, forming the Connecticut portion of the Southbridge and Blackstone. [The first map showing the New York Central Railroad crossing the South Bay is the 1854 Plan of the South Bay Showing the Harbor Commissioner’s Lines.]
The extension from Blackstone southwest to Mechanicsville, Connecticut on the Norwich and Worcester Railroad was completed in 1853. In January 1855 the new main line to Boston was opened, but was closed six months later until December 1856 because of an injunction due to the danger of the numerous grade crossings. The new line ran to a terminal at the foot of Summer Street in downtown Boston via South Boston. The full line was first operated as one on June 1, 1855, but again failed quickly. On August 6 operations were restarted on only the original Dedham-Blackstone line, operated by the Boston and Providence Railroad as a branch. On March 2, 1857 the trustees took repossession, ending the operation by the B&P. The East Thompson Railroad leased the line, reopening it again in full for about a year before another failure. At that time, all but the original Dedham-Blackstone line and Medway Branch were closed until 1867. The closed lines were sold in November 1858 to the Midland Railroad, but were not operated due to bad condition. The Midland Land Damage Company tried again in 1862, changing its name to the Southern Midland Railroad in 1863 without success.
Combined routes from Providence and Boston: 1863-1898
In May 1863, the Boston, Hartford and Erie Railroad was chartered to take over operations of the failed lines and continue the line west to Fishkill, New York, with a car float from there to the Erie Railroad at Newburgh. It quickly leased the Hartford, Providence and Fishkill Railroad from its trustees, giving it a line from Providence west to Waterbury. In September of that year it acquired the former Boston and New York Central Railroad, but did not operate it yet; the old Norfolk County Railroad continued operations by its trustees.
In the meantime, the New York and Boston Railroad had built a line from Brookline, Massachusetts (outside Boston) southwest to Woonsocket, Rhode Island, crossing the Norfolk County Railroad in Blackstone. On January 4, 1865 the BH&E absorbed that company, making its Woonsocket Division. On December 13 of the same year, various Erie Railway men were elected to the BH&E board, placing it under partial control of the Erie.
On February 11, 1867 the BH&E leased the Norfolk County Railroad, finally reopening the full line from Mechanicsville to Boston. That same year, the branch to Southbridge (part of the original Southbridge and Blackstone charter) opened. The Norwich and Worcester Railroad was leased in 1869, finally giving it a route to Boston, using the N&W from the Providence line at Plainfield north to the old Norfolk County Railroad at Mechanicsville. In August 1872 a direct connection from Willimantic on the line to Providence northeast to Mechanicsville opened, completing the direct line to Boston.
The lines now serves as commuter rail through the MBTA from Readville to Boston and is known as the Fairmount Line.