If you have been to Cambridge, you've seen bricks. Lots and lots of bricks. It's clear they're a part of the architectural aesthetic of New England and of this city, but another reason bricks are omnipresent is that they're a local product. In the nineteenth century, most of North Cambridge was dug up for brickyards.
Brick had been used in New England since the colonial period, because it was stronger than wood and very fire-resistant. It was cheaper, lighter, and easier to find locally than quarried stone. Brickmaking was a large industry in present-day Medford beginning in the 17th century. In those early years, that area was still a part of Cambridge, which is why some will tell you that this city has been making bricks its whole life. If we look only within the modern borders of Cambridge, however, brickyards did not appear until the 1840's. In the mid-nineteenth century, there was a new market for bricks: they were the building material of choice for large factories.
North of Harvard Square and west of Porter Square, the North Cambridge areas that became brickyards had always been thought undesirable. The land was swampy and bad for farming, although most of it was owned by farmers. It turned out that this area was rich in clay, the raw material for a profitable industry. In 1844, Peter Hubbell and Almon Abott leased some of this land and created a brickyard. When it proved successful, it sparked a “clay rush” as entrepreneurs took notice and entered the brick industry. Some of the most famous companies were the Bay State Brick Company and the New England Brick Company, but by the end of the century, the area had at least half a dozen companies operating side by side. The Cambridge Historical Society has some great photos of the New England Brick Company.
Like the industrial populations of East Cambridge and Cambridgeport, the laborers in the brickyards were chiefly immigrants. North Cambridge was nicknamed “Dublin” and “New Ireland” around the Civil War, because of the number of Irish immigrants working and living there. By the late nineteenth century, Irish-Americans were beginning to use their numbers for political clout, and the descendants of impoverished immigrants were starting to make it into the middle class. By this time, the local brick industry was starting to decline, but it still needed workers, and French Canadian and Italian immigrants became the biggest populations in the brickyards.
The brick industry in Cambridge used the soft-mud method of making bricks, which is the “handmade” way and the most common method during the nineteenth century. In the soft-mud method, workers first plow the ground, then soak the clay in water and sand for about a week in a “soaking pit.” Then the material is beaten – a difficult process done in a large apparatus called a pug mill (ceramics enthusiasts will recognize some of these early steps, as clay used for pottery is treated similarly). The pugged clay is then put into molds that are coated in water or sand to prevent the bricks from sticking to the molds, and sun-dried. After being dried once, the bricks are laid on flats for more drying and finally fired in a kiln. The firing took more than a week, and after it was completed, the whole kiln, which was made of bricks itself, was often disassembled. A brickyard worker generally had a specific task that he performed, and so there were many specialized job titles for the laborers, including clot moulders, off-bearers, and edgers. The process used became more advanced as the Cambridge brick business grew. In the early years, men moved clay with shovels and wheelbarrows alone. Later, donkeys, horses and even trams helped the workers move larger quantities of clay.
While there was a continued demand for bricks as long as factories were being built from them, the brickyards in Cambridge were most active in the middle of the nineteenth century. Brickmaking went through expansion and recession cycles that followed the economic climate of the country, and the brickyards were particularly hard-hit by the Panic of 1873 and that of 1893. Local brickmaking went into its last period of decline after the Second World War. Many of the clay beds, which could get to 80 feet deep, were spent. From the 1950's through about 1970, the city used some of the former brickyards as landfills, while others were still active. No bricks have been produced in Cambridge in the last 40 years.
Many of the bricks used in buildings and sidewalks in Cambridge are local. On some, you can see the stamp that indicates the brand, but generally, the branded side of a brick is the side placed out of sight. Most brands are the name or initials of the company, but some use a symbol. Here's a branded paver (brick used in paving a street) from near Harvard Square:
Abstract symbol, or a stylized "H+G?" "H+C?" I have not found information on a brick maker with those initials, but either one is possible.