The Oldest Tunnel in New York City

There are a variety of types of tunnels that can be built. Primarily they are the cut and fill and the true tunnel.  In the cut and fill method, which is used because it is much cheaper to construct, a trench is dug, the tunnel walls and ceiling are constructed of masonry or other materials, and then the earth is returned to the trench to "bury" the tunnel.  The true tunnel is constructed by literally digging from one end to the other (or, more often, digging from both ends towards the middle). Some true tunnels are dug in dirt, and others through stone. The advantage of stone, many times, is the lack of need for a supporting structure, but the disadvantage, of course, is that the tunnel must be cut from the very strong stone, which makes it much more difficult and time consuming, not to mention the cost.

The oldest true tunnel in NYC for rail traffic, or any kind of traffic, is the Mount Prospect Tunnel in Manhattan, opened in 1837. It now forms the center two tracks of Metro North from 92nd St. to 94th St. under Park Ave. The tunnel north and south of it, and the one-track tunnels on each side of it, were added in 1873-1875, but the Mount Prospect Tunnel was left in place and became part of the larger “Fourth Avenue Improvement”

The following illustration that appeared in the November 14, 1874 issue of the Scientific American shows the ground elevation and other pertinent information on the underground rail line from 42nd St to the Harlem River which was completed in 1875.  Of course, Fourth Avenue, became Park Ave.

In the center frame I have enlarged below you can clearly see that the section between 92nd and 94th Streets is labelled "Rock Tunnel."

Interestingly, the area that the Mount Prospect Tunnel is located is now called the Carnegie Hill area of the upper East side of Manhattan.  That name, Carnegie Hill, became the new name for Mount Prospect after Andrew Carnegie purchased land (1897) and built his residence (1903) at 91st Street and 5th Ave., a few blocks away from the tunnel.

The Atlantic Avenue Tunnel (also referred to as the Cobble Hill Tunnel) in Brooklyn was built in 1844-45 and is touted as the oldest Railway Tunnel in the world, it has been cited that the Mount Prospect Tunnel, while having been built earlier, was originally built for street cars and only converted to be a railway tunnel in the mid 1870s.

Cobble Hill Tunnel

There is a belief that a true tunnel was constructed for the Croton Aqueduct in upper Manhattan which opened in 1842, but that has not been documented as of this writing. Clearly, that tunnel, if it exists, was not for traffic at all, but rather a viaduct for water and appears to be constructed around five years after the Mount Pleasant Tunnel was completed.

The Abrams Universal Sun Compass

I have had an Abrams Universal Sun Compass in my  collection for quite a few years now. Shortly after I got my Abrams, about 10 years ago, I  searched for the company and found that they were still  in business in Lansing MI.  In the directions that come with  the device it explains how to adjust the sundial to get a  correct reading for each day of the year.  I have a pretty  good understanding of sundials and know why that is the  case.  There is a plate on the device that has the dates for  adjusting for the specific days for that specified year.  I was  wondering if they continued to make additional plates for  other years.  --- and how many years did they continue  to produce them.  I called the company and I spoke to  someone there about the item.  After describing the item  and what I was looking for she broke out into laughter.   Nobody had asked her for one of those since the end of WWII.   I was amazed that she had been there that long and that she  remembered the item.  Anyway, I got a good laugh out of it  too. The following information is contained in a post at  Collecting Military Compasses, and was provided by Ted Brink  for inclusion here thanks to his permission: The U.S. Army Sun Compass was produced during WW2 in  the early 1940s by Abrams Instrument Co. of Lansing, MI,  designated Model SC-1. In operation, it could determine  direction accurately by noting the angle of the sun at a known  time of day. It was designed for daylight use, but could   navigate at night by orientation to the Polar star, mounted on a  vehicle in environments where a magnetic compass might not  work properly, such as inside an aircraft or truck due to the  metal content or electrical circuits nearby.The exterior of the  box is painted olive drab and the lid is lettered:                         C. of E.                                      U.S.A.                              SUN COMPASS The  C. of E. stands for the U.S. Army Corps of Engineers,  responsible for military compasses and other instruments  during World War II.

In World War II the SC-1 was used in the North African 
desert by the Long Range Desert Patrol (the famed Desert 
Rats) and other American, British or Australian units. Other 
uses were in B-24 Liberator bombers and by Army ground 
troops in the Philippines. It is reported to have been used 
through the 1970s for polar region expeditions where 
magnetic readings are unreliable or in the Sahara desert.

company is still in operation today but it has not made this instrument for a long time. Abrams Instrument

specialised in instruments for the aviation industry and made the Sun Compass under contract for the American

government during the Second World War. (The manual in our possession is dated 1943)

Liberator bombers were equipped with this instrument so that, in case of a crash, the survivors could orientate

themselves in the desert.

o 

45° north and south of it, in 3° divisions. Several different length styluses were provided, the tallest of which 

would have been used within the tropics and the shortest in conjunction with the others for night navigation by 

orientation to Polaris, the north polar star. The tips of the styluses contained a tiny glass capsule apparently filled 

with a luminous substance and was presumably used at night but its exact function and method have yet to be 

discovered. The date plate was calibrated for both northern and southern latitudes. Thus the instrument was 

which American patent 2441636 later applied.11 It was calibrated for both hemispheres and from the Equator to 

45° north and south of it, in 3° divisions. Several different length styluses were provided, the tallest of which 

would have been used within the tropics and the shortest in conjunction with the others for night navigation by 

orientation to Polaris, the north polar star. The tips of the styluses contained a tiny glass capsule apparently filled 

with a luminous substance and was presumably used at night but its exact function and method have yet to be 

discovered. The date plate was calibrated for both northern and southern latitudes. Thus the instrument was  3

most others. 

 

immediately usable in either hemisphere and so was consistently universal within its calibrated latitudes, unlike 

The Sun Compass was manufactured by the Abrams Instrument company in Lansing, Michigan, USA. The

company is still in operation today but it has not made this instrument for a long time. Abrams Instrument

specialised in instruments for the aviation industry and made the Sun Compass under contract for the American

government during the Second World War. (The manual in our possession is dated 1943)

The Sun Compass seems to have been used mainly in the North African desert by the American Army. B24

Liberator bombers were equipped with this instrument so that, in case of a crash, the survivors could orientate

themselves in the desert.