Revere’s metalworking experience, in this case his iron foundry work and his earlier silverworking, again proved directly relevant to the new field he wished to enter. Armed with his iron-casting knowledge, he now faced several new learning objectives: learn how bronze differed from iron throughout the heating and cooling process; practice the casting of larger objects; acquire some bell molds; and experiment with acoustics. Because copper and silver have some common properties, his silverworking career offered guidance about how to cast copper alloys and how they differed from iron. For example, iron hardens when it cools quickly, while copper and silver soften.18 Revere’s general understanding of metal casting allowed him to focus on updating and honing his knowledge rather than spending time learning the basics. He addressed his highest priority, the acquisition of bell-related molds and patterns, with several purchases recorded in his ledger as “core moulds,” “patterns of crown of 3 small bells,” and “patterns of crown of large bell.” He also purchased sand, clay, and other patterns that might have applied to either iron casting or bell making.19 All of Revere’s correspondence, discussions, and equipment prepared him to enter this trade, but nothing could replace the value of experimentation and personal experience. Complaints about Revere’s first bell remind us that practice makes perfect, and the lack of complaints regarding his second and later bells attests to his continual improvement.
Revere’s first bell contract with his own parish gave him the opportunity to learn the basics of the bronze-casting process in a supportive environment. Although the bell’s shrill tone and surface imperfections did not prevent him from getting paid, he clearly had ample room for improvement. Revere and his workers stepped up to the challenge and eventually mastered the details of one of the most complex and unforgiving metalworking processes practiced in eighteenth-century America.
Bell makers first created an inner core that modeled the inside diameter of the bell. They accomplished this by digging a hole in the ground, building a hollow pile of bricks in the center, covering them in a special mud, and using a pattern to pack the mud into the precise shape of the interior of the bell. Second, they applied a mixture of tallow and wax to the outside of the core, creating a perfect wax model of what the finished bell would look like, including lettering or designs. Third, workers applied numerous coatings of “bell mud” on top of the wax, creating the shell, a model of the outer surface of the bell. The shell pressed right against the wax model and hardened against it, conforming to its exact shape. At this point the workers had created a mud core resembling the bell’s interior, a wax middle layer that modeled the final bell, and an outer coating of mud on top of the wax. A workman then lit a fire inside the hollow brick structure at the center of the core to melt the wax and harden the mud: the core and the shell now resembled the inner and outer surfaces of the bell, separated only by air. The shell was then hardened with additional fire, and covered in sand or loose soil to prevent it from bursting. Casting experts then poured molten metal into the space between the core and the shell. After it cooled, which would require a day for bells weighing up to a ton and up to a week for larger ones, workmen removed the bell and trimmed any casting irregularities. Holes, pockets of air, or cracks in the core or shell could ruin the bell at any stage of this process. Finally, craftsmen began the laborious process of polishing and tuning the bell. They painstakingly smoothed the inner and outer surfaces, and removed small quantities of metal at different points to prevent partial notes from interfering with the tone of the fundamental note.20
Although Revere and his workers grew more proficient and confident with practice, the bell-making procedure did not lend itself to standardization. Revere’s correspondence and records show that he probably used existing bells as models for new ones: he refers at points to the weights and dimensions of some of Boston’s church bells when discussing a new contract, and his bell sales include clusters of bells with similar weights that probably followed the same general pattern.21 Each bell required its own mold that did not survive the casting process, and every step of the mold-forming and casting process needed careful attention and adjustment. For example, the mud used to pack the bell mold had a special formula that optimized its moisture content, density, and other properties, recorded as a recipe in his 1793 memoranda book: “The mud for thickness of Bell one part horse dung one Sand & one part Clay For Navel & Cope 6 parts horse dung 4 Sand & 4 Clay & some Cow Horn.” Revere’s crew had extensive experience with the preparation of smaller molds for iron casting, but bell molds occupied many cubic feet and had to receive hundreds or thousands of pounds of molten metal.22 Each mold required days to prepare, and therefore an error during the casting process became costly.
Revere practiced this new trade alongside his iron-casting work, getting double use out of the foundry oven he had already constructed while taking advantage of his workers’ familiarity with metal casting. According to Reverend Edward Griffin Porter, who captured various recollections about Boston history in his 1887 book Rambles in Old Boston, Revere used the backyard of his nearby Charter Street house to display and sound some of his finished bells. This text states that Revere’s property
Figure 5.1. Lowering the shell and forming the bell core. From Denis Diderot and Jean le Rond d’Alembert’s Encyclopedie: Recueil de Planches, sur les sciences, les arts libéraux et les arts méchaniques aves leur explication (Quatrieme Livraison; Paris; Briasson, David, LeBreton; 1767), vol. V, “Fonte des Cloches,” plate II; as cited in Charles Gillispie, ed., A Diderot Pictoral Encyclopedia of Trades and Industry, vol. 1 (New York: Dover Publications, 1987), plate 115. Beginning in the 1750s, Denis Diderot’s multivolume Encyclopedie illustrated the equipment and processes used in many French trades. This illustration depicts several stages of the bell-making process that some founders still followed in Paul Revere’s time. On the left, workers (not pictured) lower the outer shell onto a finished inner core. On the right, two workers use a mold to produce another core. Once the shell and core are properly aligned, bell founders pour molten metal into the space between them to form the bell. Other founders used wax to initially fill the space between the shell and core, and melted the wax with a fire before pouring the bell metal.
was about sixty-four feet wide and one hundred and forty feet deep, containing a large yard in the rear, where bells were often placed for inspection after being cast in the foundry. Purchasers would come to hear them sounded; and boys would often gather round out of curiosity. One of their number remembers being present with others on such an occasion, when they were probably in the way; for Mr. Revere pushed them aside with his cane, saying: “Take care, boys! If that hammer should hit your head, you’d ring louder than those bells do.”23
One of these boys was probably his son Joseph Warren. Born in 1777, Joseph Warren had some silversmith training but also spent time in the foundry, which he eventually supervised. Older son Paul Jr., by this point an adult in charge of most aspects of the family silver shop, also helped out in the bell foundry. He apparently preferred bell casting over silverworking since he left the family business to run his own bell foundry in 1801.24 Revere ran each of his businesses as a family concern, illustrated by the use of his own house as a bell showplace, and in the case of something as audible and fascinating as bell casting, the business became something of a neighborhood draw as well. Revere’s open shop policy remains consistent with the practices at many other establishments, some of which offered invaluable aid to him with each new endeavor.
Alongside his growing technical expertise, Revere’s marketing savvy increased. He devised a one-year warranty policy to aid this new trade, initially offered on all church bells:
This bell is warranted for twelve months accidents & improper usage excepted; and unless it shall be rung or struck before it is placed in the belfry, or tolled by pulling or forcing the tongue against the bell, by a string or otherwise.25
This simple statement illustrates a major shift in early retail policy, in w
hich Revere backs each item with a guarantee of quality. His shrewdness comes across in the “accidents & improper usage” exception to this warranty, because he did not want to spend his shop’s time and money fixing breaks caused by common user errors. The most frequent mistake receives explicit mention in his policy: many bell ringers rang their bell in the easiest manner possible, by grabbing a rope attached to the bell’s tongue and smashing it into the side of the bell. This improper ringing technique prompted Joseph Warren Revere to write, “with a yard of twine I would undertake to break every Church bell in Boston.”26 English bells, including ones made by Revere, should have been mounted on a large wheel that, when turned, swung the side of the bell into the dangling clapper or tongue. The tremendous weight of these bells made the installation process somewhat challenging, especially for churches that had not previously owned one, and Revere’s warranty also takes care to exclude accidental damage because these bells would not survive a long drop or similar mishap. Upon selling each bell Revere probably discussed the details of their use and upkeep with the buyer, and this warranty helped him underscore the most important points.
A second note elaborates several of his pricing policies:
Price of Bells
All bells of 300 lbs and over are to be warranted as Church Bells, and the same discount made for cash. All under 300 lbs, or all sums less than one hundred dollars, 60 days credit or one pr cent to be discounted for cash.27
Revere extended a warranty only to church bells and the largest school bells and also offered a cash discount of 1 percent. The cash discount may appear trivial by modern standards, but represented another new step for Revere, as he realized that the continued extension of credit hurt his business. Departing from complex silver shop dealings in credit, barter, and cash, he now attempted to move to a fully cash system.
Revere finished his first bell in 1792, and sold five the following year. He made three types of bells, with different sizes befitting their different uses. Church bells, by far the largest and most complicated, weighed more than 500 pounds and occasionally exceeded a ton. Schoolhouse bells usually weighed between 100 and 500 pounds, though rarely more than 300 pounds, and ship bells weighed 100 pounds or less.28 Table 5.1 presents the bells made by Revere’s foundry until 1810, the last full year of his employment, as recorded in his own painstaking tally in two different ledgers in his family papers.29 He probably ended his personal involvement in the bell-making process earlier than 1810, but this table records the entire production line completed during his active career, including church, school, and ship bells.
Table 5.1 reveals repeated fluctuations from year to year, with the fewest bell sales in the first three years and the highest number of sales between 1798 and 1808. This irregularity resulted from Revere’s other responsibilities as well as the changing economic climate. Following the startup period of the first three years, the low output of two bells in 1799 probably reflects Revere’s preoccupation with federal contracts for cannon, bolts, and sheeting, while the economic recession most likely caused the 1804–1805 lull.
Bell making certainly had the potential to bring in good money, but Revere could not count on it for a steady income: he never sold a large number of bells in a given year and the demand fluctuated too much. Each bell yielded a considerable degree of profit, in keeping with its status as a finely crafted item. Revere’s bell price changed over the years but usually remained between 42 and 50 cents per pound of bell weight: typically 45 cents (or 2 shillings, 8 pence) per pound for church bells, and 50 cents per pound for smaller bells. Revere typically charged around 50 cents a pound for pure copper items such as bolts, spikes, and sheets, which made his church bell price something of a bargain, possibly reflecting an economy of scale when casting larger items.30 Without a record of Revere’s labor costs we cannot determine the profit that he realized on each bell, but as with all of his high-weight products, bells generated large income surges with each sale. He surely appreciated this addition to his product line, and for reasons beyond the monetary.
Table 5.1. Revere’s Bell Production and Weights
Unlike his increasingly standardized silver-rolling and iron-casting activities, bell making was a more artistic activity requiring immense amounts of skilled labor and customized attention for each piece. In this case a step backward in terms of mass production still equated with progress in other areas, such as high-profile visibility and distinction for the Revere shop. Even Revere’s earliest bell, with a tone that made some listeners squirm, represented a manufacturing achievement for Boston and a triumphant accomplishment for its founder. This first bell still rings twice a year, on Good Friday and Christmas Eve, in the St. James Episcopal Church in Cambridge. More than one hundred other bells made in the Revere shop survive to this day, praising the skill of their maker with each chime.
Cannon Founding and Government Contracting
In 1794 Revere made the next evolutionary step in his career by entering the cutting-edge field of cannon casting. One might be hard pressed to imagine a larger ideological shift: shortly after learning to cast bells that created beautiful music, transmitted vital information, or summoned townspeople to church, Paul Revere began receiving commissions from state and federal war departments seeking the most destructive weapon of the eighteenth century. Without hesitation the almost 60-year-old entrepreneur plunged into this new field, perhaps because his military background helped him understand the strategic importance of cannon, or possibly because he realized that both church bells and cannon served societal needs in a prominent manner. This new trade dominated his shop within a few months.
Cannon casting was the quickest and easiest technological leap of Revere’s lifetime, as attested by his speedy mastery and the dearth of written materials in the Revere Family Papers pertaining to his learning process. Cannon casting used almost identical raw materials and equipment as bell making: throughout the history of European warfare innumerable invading armies tore down the church towers of their enemies and recast bells into usable artillery. In addition to Revere’s experience with the casting of large bronze and iron objects, he also had some exposure to cannon-specific techniques and tools, such as cannon molds from his earlier work with Louis de Maresquelle at the Titicut furnace in 1777. In addition, Revere had a working familiarity with the use and limitations of different types of cannon from his service as an artillery officer in both the French and Indian and Revolutionary wars. We can safely assume that he carried out his typical research process by consulting several of his knowledgeable colleagues, obtaining some molds, and experimenting until he mastered the new technology. As with the bell-making trade, cannon casting had not reached the state of maturity in America to enable a large or connected community to form, forcing Revere to learn complex processes largely through trial and error. In Europe, however, cannon casting held an exalted status as one of the fields that ushered in the era of centralized nation-states.
The first cannon originated in ancient China, as did so many other technologies. Chinese alchemists developed the first usable gunpowder around the ninth century AD, and developed metal-barreled cannon to use this gunpowder at some time in the twelfth or thirteenth century. Early cannon resembled metal vases that fired arrow-shaped projectiles, and this technology soon spread through the Middle East and into Europe. While cannon are depicted in some European texts and played a small role in several early engagements, they first became vital strategic weapons in the Hundred Years’ War in the fourteenth and fifteenth centuries when France used large numbers of cannon to defeat and evict invading English armies, often by shattering formidable static defenses such as castle walls. Modern observers would recognize many aspects of these early cannons: French armories cast a tubular cannon body in a single piece instead of attempting to weld together a series of bars; bronze and brass became the choice construction materials due to their favorable material properties; and spherical cannonballs often made of stone became the dominant form of ammuni
tion. The rapid spread of cannon led to a European arms race and a “second bronze age” in which the nations able to lay hold of reliable copper, tin, and zinc resources gained a strategic advantage, even after England improved its ability to cast iron cannon in the sixteenth century.31
Cannon technology took a great leap forward in the 1460s and 1470s thanks to pioneering metalworkers in France and Burgundy. Size became the critical design constraint: cannons to date had been immense and often immovable devices, useful when they could be cast near the site of use but not suitable for field or mobile needs. A series of complementary developments enabled cannon casters to greatly reduce the amount of metal they had to use while also increasing their weapons’ overall destructive power. Advances in gunpowder manufacture led to the use of small grains or corns of powder that produced bigger explosions, and iron cannonballs replaced stone ones. Along with the use of mobile gun carriages to facilitate the transport of heavy weapons, the newly mobile array of siege weapons reconfigured the power structure of Europe, giving attacking forces a new advantage over defensive fortifications. In addition, large and centrally organized countries reaped the biggest rewards because only they could raise enough funds to support constant purchases of new weapons. The Senate of Venice gave words to this military paradigm shift in 1498, declaring, “the wars of the present time are influenced more by the force of bombards and artillery than by men at arms.” Lighter-weight cannons also functioned well on ships, which now became potent mobile weapon platforms. The considerable weight of large numbers of cannon ran the risk of making ships too top-heavy, but this could be mitigated by cutting gun ports in hulls and placing heavy weapons closer to the waterline. King Henry VIII of England financed the first of this new class of warships, which inaugurated a naval revolution that eventually led to European, and specifically English, dominance of the high seas. England’s and Europe’s advanced metallurgical technology became a crucial advantage in Renaissance-era warfare, with numerous contemporary reports (supported by modern chemical analyses) praising the strength and durability of Western bronze and iron in comparison to more brittle and overly bulky ordnance captured from the Middle East and India.32 Britain guarded its cannon-casting technology even more strictly than its other technological secrets due to its strategic importance to the empire’s worldwide interests. While the American colonies benefited from access to British arms throughout the colonial years, the ability to create these weapons remained entrenched in the mother country, which had major impacts upon the Patriots’ ability to carry on their Revolutionary struggle.
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