The Flames.

The period from 1775 - 1825 was known as the golden age of stone wall building.
During this time period, more stone walls were built than any other period of time.

This period of time was also when more and better designed stone walls started to take the place of older stone walls. The increase of stone wall building during this period of time is due to a few factors.
The main reason for the increase was directly linked to an increased interest in farming in New England.
The increase in stone wall building from 1775-1825 is also the direct result of population increase.
New advances in travel and farming allowed stone walls to be built faster.

The type of rocks that masons used to build stone walls in New England varied.
Most of the time the rocks that were used in a wall were granite, limestone or gneiss.

These rocks were the most popular to use because they were found in abundance across New England.
These are also the few types of rocks found in New England.
When a mason or a farmer requested rocks, they usually had to be drilled or mined out of caves.
A substantial amount of rocks used in stone walls were also those found in farms and in woods.

The reason why so many stones were found throughout farms and woods is because of glaciers.
When the glaciers were formed, they trapped many rocks within them.
When the glaciers melted across New England, they would dump millions of tons of rocks in random places such as woods or land that would be used as farm later on.

The only types of rocks that could survive a glacier are the really hard ones, such as granite and gneiss.

Glaciers also left many fieldstones and other rocks rather smooth because a glacier would tumble and tend to smooth out many rocks.
Because of the round shape of these rocks, they were not very useful in building walls.
The rocks that were not rounded however, were very hard and durable once put in a wall.


Granite
Granite is the most common rock found throughout New England.
Granite is extremely hard and did not smooth out easily, which made it the optimum rock of choice with which to build walls.
There are three categories out of which a rock could fall under: igneous, metamorphic and sedimentary.
Granite falls under the both the igneous and metamorphic class of rocks.
Igneous rocks are formed by the cooling and hardening of magma found within the earth.
As the magma cools, most rocks will already be hardened or crystallized.
The last rocks to crystallize are potassium feldspar, muscovite mica, and quartz,
which are the major components of granite.

Rocks also fall under the categories of acidic, intermediate or basic.
Metamorphic rocks are formed under particular temperature, pressure, and chemical conditions that produce rocks with different textures and minerals.
These rocks are formed under the earth's surface by great stress and high temperatures.

Granites show evidence of both thee igneous and metamorphic processes.
Some granite has a crystallized melt form, which is found only in the igneous process.
Other granites however, show evidence that they were formed through the metamorphic process.
The metamorphism of a granite rock is called granizitation.


Gneiss
Gneiss is another important rock used in building stone walls. Gneiss is similar to granite in that it is formed through the metamorphic process, and that it can survive a glacier.
Gneiss is different in other ways. Gneiss is formed by the magma in the earth heating up as opposed to granite, where it is formed by magma cooling down.
Gneiss is a coarse rock and is usually not very smooth.
Gneiss is also a rock with very distinct banding,
usually of light and dark layers, and forms when the atoms of minerals break down chemically, segregating into different layers, each of which with its own distinct mineralogy.


Limestone
Limestone is another metamorphic rock found in the building of stone walls.
Limestone is an extremely basic type of rock that is found in few stone walls.
Most limestone found in a stone wall is used as mortar or is put in accidentally after being mistakenly identified as granite or gneiss.
It is rather brittle and is not very useful. "Limestone consists of consolidated carbonate muds precipitated from seawater or of carbonate skeletal remains of marine organisms".

The third type of rocks are sedimentary.
Sedimentary rocks tend to be created by weathering from the elements. Sedimentary rocks are formed by the heating of magma in the earth,
weathering from wind and water, and breakdown caused by intense pressure from the earth.
Sedimentary rocks tend to be rather brittle because of all the weathering they have endured.
Because of this, most sedimentary rocks are not very helpful when building a stone wall.

Gravel is one of the few sedimentary rocks that are helpful in building a stone wall. Gravel can be placed under a stone wall in a trench to prevent the wall from easily moving or sinking.