Stabilization of the Oxford Furnace
Oxford Furnace previously underwent a 4-year stabilization project under a $315,000 grant from the New Jersey Historic Trust, with additional funding from the Warren County Freeholders.
Construction of this National Register site began in 1741 and the Furnace went into blast on March 9, 1743. The Oxford Furnace was the third furnace built in the colony of New Jersey. When it was blown out for the last time, in 1884, it had the distinction of operating longer than any other colonial iron furnace. Oxford’s longevity was due to the successful conversion from the burning of charcoal for fuel to the use of anthracite coal.
This county treasure was the site of an important “first” in iron history and technology: on May 24, 1835, William Henry achieved America’s first successful “hot blast.” Early uses of steam-heated blasts and turbo-power were developed by later owners of Oxford’s iron and mining businesses.The first step in the stabilization process was that of cleaning out the furnace bosh. The photographs below show the scaffolding atop the furnace which was used to hoist the debris out of the bosh. The bosh is the main internal furnace cavity where charcoal (or later coal), limestone and iron ore were placed during furnace operation. Approximately 65 tons of sand, firebrick and stone were removed from the bosh. Most of this material fell down inside the furnace from the upper portion while it was idle and slowly deteriorating. This furnace has been idle since 1884. Some stabilization work was done in 1980 after a large portion of the furnace side collapsed.
On Thursday August 2, 2001, the last of the 65 tons of debris were removed.
The following photograph is taken from the furnace top looking down inside.
The furnace hearth, which is at the very bottom of the furnace where the molten iron accumulates, has not been excavated. It appears to be intact. The hearth excavation will not be performed at this time.
This furnace has three side openings, called Tuyeres (pronounced like “two years”), for blowing air into the furnace. A fourth opening, called the casting arch was used to remove molten iron and slag from the furnace. Two of the tuyere openings are now open and contain no historic remains on the blowing apparatus. The third however may contain the nozzle used to inject this air into the furnace. As with the hearth, excavation of this area will not take place at this time.
The job contractor, DeGruchy, is aided by Historic Preservation Consultant, Carla Cielo, and Industrial Archeologist, Victor Rolando. Both Carla and Victor feel this furnace is a very important one, due to the fact that the bottom area of the furnace is intact and untouched since 1884. Excavation of this portion must be carefully planned and thought out.
The photograph below is taken inside the furnace looking up. The area we see is called the bosh. The block you see at the top of the photograph was installed during the work done in 1980 and is not original to the furnace operation. Just below the block you can see the original bosh wall. This wall is made of firebrick glazed with fireproof clay. Attached to this clay is the remains of some moltent material which attached itself to the wall.
Tuyere openings are shown in the following photographs.
The image shown next it the South tuyere opening as shown from the outside of the furnace.
Next we see the same tuyere opening as seen from the inside of the furnace.
An exterior view of the casting arch opening is shown below.
Now we see the inside view of the casting arch as seen from the inside.
By November 2001 workers had installed scaffolding and began the tedious task of removing all the old loose mortar or mortar containing the 1980 installed Portland Cement. They then replaced the old mortar with the new historic type lime based mortar.
The repointing of the mortar was completed. As you can see in the following photographs, the mortar between the stone on the entire lower portion looks very good. The contractor is removing the scaffolding in preparation for the addition of the low pitched roof.
The low pitched roof construction is now well underway. The built-in gutter structure can be seen in the last photograph.