Roman oil lamps

Why oil lamps? In a world without electricity, artificial light is limited. People lived between sunrise and sunset. Unlit nights were not only dark but also dangerous. Without an active police force, crime lurked everywhere in Roman cities. Fortunately, there were oil lamps, which provided sufficient illumination during this period of darkness to still enjoy the luxury villa in the evening. It is not surprising that the Roman oil lamp played a prominent role in society and therefore tells us much about how people lived in classical antiquity. 

An oil lamp is a lamp that produces light over an extended period using an oil-based fuel. The use of oil lamps began thousands of years ago, at least during the Chalcolithic period, and continues to this day. Fuels for oil lamps include a wide variety of plant sources, such as nuts (walnuts, almonds, and kukui) and seeds (sesame, olive, castor, or flax). Animal fats were also widely used, such as butter, ghee, fish oil, shark liver, whale oil, or seal fat. In classical antiquity, animal fat and natural olive oil were primarily used.

An experiment with replicas's of Roman oil lamps shows that small oil lamps need to be refilled every few hours. Larger lamps only needed to be refilled once a day, and new wicks needed to be replaced even less frequently.

Lamps needed a new wick and extra oil, often every day or even more frequently. Another flame was used to light the lamp if it had gone out. It is known that lamps were brought to a room during meals, which may mean they were first in the kitchen or another space, and then brought to the dining room when needed.

At a dinner, it was often discussed the custom of not blowing out lamps. Plutarch writes about a Roman custom of keeping lamps lit during meals, so that there was still light after eating. Someone else says that a man had his lamps refilled immediately when they went out, so the slave could check if the oil was not stolen.

Many lamps were quite small and could not hold much oil. Some lamps had a filling hole at the top – a small hole in the shape. In many bronze lamps, this hole was quite large and clearly separated from the wick hole. Other bronze lamps had a filling hole that was almost as large as the wick hole, but often much smaller. In earthenware lamps, the filling hole was usually smaller than the wick hole, sometimes even much smaller, but in some lamps it was deliberately made larger, possibly because users were annoyed by the small hole. In many cases, the oil seems to have simply been poured through the larger wick hole.

An earthenware pot, with a round, closed shape and a low spout, is sometimes seen as a special filling pot for pouring oil into the lamp, but the shape is also recognized as a drinking bottle for children or sick people.

In fact, any small earthenware container can be carefully used to pour oil for burning. However, this is dangerous and does not provide a consistent light source. Therefore, most oil lamps had the well-known pointed design. This way, the oil does not quickly flow over the edges or burn up too quickly. 

Another important point is the length of the wick. A simple flat wick was probably used most of the time. Wicks that were too long caused smoke and a burning smell. Juvenal describes how unpleasant it is to smell like school because you worked with a lamp, and says that boys often stank of lamp oil. Horace complains that he is completely black from the soot, just like Virgil. Sometimes scented oil was used in lamps, but this does not seem to have been common. The wick of oil-burning lamps did not need to be maintained as often as that of a candle made of animal fat, but every few hours it still had to be pulled up a bit. This was tricky because you didn't want to burn your fingers. 

Some lamps had a slot or hole specifically for an awl (a thin stick) with which you could pull up the wick.

A farmer said he always removed the old wick with an awl and then inserted a new one into the oil hole. Some lamps have been found with metal pins nearby, which were probably used for this purpose. Perhaps some pins in archaeological finds also served this purpose, but it is difficult to say with certainty.

In the sixth century AD, a man from Alexandria designed a lamp with an automatic wick feeder, much like modern mechanical devices. But in everyday use, the shape and design of lamps changed little during Roman times.

Archaeologists identify oil lamps from classical antiquity based on basic typology. There are various archaeological typologies used worldwide. Loeschcke Typology (1919), Bailey Typology (British Museum), Hayes Typology (for North Africa / Tunisia) are probably the most well-known. In this blog, we use the Bailey Typology.

Greek oil lamps are more enclosed to prevent spillage. They are smaller and more refined in shape than predecessors from European Bronze Age. Most do not have a handle. Some are equipped with a lug, which may or may not be pierced. The spout is extended. The rim of the lamp is folded over to overlap and form the spout, and then pinched to create the wick hole.

The production of oil lamps shifted in the early Roman period to Italy as the main supplier. Molds were used, and the lamps were mass-produced in workshops or factories. All lamps from this period are of the closed type. The lamp is made in two parts: the upper part with the spout and the lower part with the fuel reservoir. Most lamps belong to the characteristic "Imperial Type" — round in shape, with spouts in various forms (volute, semi-volute, U-shaped), a closed body, a central disk decorated with reliefs, and a filling hole.

Type A includes the oldest Roman oil lamps from the typology. These date from the late Republican and early Imperial period (circa 1st century BC to 1st century AD). These lamps are simple in form and often quite robust. They usually have one spout and a wide oil holder, with little decoration. This type marks the transition from handmade to molded lamps and sets the basic for later, more refined designs.

Type B lamps are representative of the 1st and 2nd century AD, a period when the production of oil lamps became more standardized and refined. These lamps are more symmetrical, often with decorative discus motifs showing mythological or natural themes s. Multiple spouts sometimes occur. They reflect the growing prosperity and the advantages of mass production. 

Late Roman oil lamps belonged to the so-called "High-Imperial" type. They were more richly decorated than earlier models and were both locally produced and widely imported. During this period, lamps with multiple spouts also appeared, allowing multiple wicks to be burned simultaneously for more light. A great variety of shapes and styles emerged.

The "frog type" also appeared in this period. These lamps are kidney-, heart-, or oval-shaped and feature the motif of a frog or an abstract representation as decoration. Sometimes geometric patterns are also added. They were produced around 100 AD. Due to their diversity, two identical specimens are rarely or never found. 

Type C includes lamps from the 3rd and 4th centuries AD, in which Roman lamps often became more massive and thicker, with rich decorations, including religious symbols such as the Christian cross. These lamps could have multiple spouts and were often produced in large factories. They demonstrate how Roman culture changed in a time of political and religious transitions.

Early Christian and late antique oil lamps show a great variety in shape and decoration. One of the most remarkable types are the Mediterranean sigillata lamps, also known as "African lamps".

Type D is characteristic of the transition from the classical antiquity to the late antiquity and the Byzantine era (4th to 5th century AD). These lamps show a diversity of forms and decorations, with a strong emphasis on Christian symbolism. Production techniques were large-scale and standardized, and the design reflects the changing religious and cultural context of the Roman Empire.

The decorations on these lamps were mainly geometric, vegetal, and graphic in nature (such as monograms), but often also depicted figurative representations of animals and human figures, frequently portraying Christ. Such as lamps with depictions of Christ or the Chi-Rho symbol.

Oil lamps from the Byzantine period often had the shape of a slipper and were heavily decorated. The design with multiple nozzles remained in use, and most lamps were equipped with handles.

Open oil lamps were usually made of pottery, but also of lead or even iron, like the lamps that hung on hooks and could be hung from a beam – this was especially common in Britain. The lamps could be hung horizontally, as in some catacombs, or vertically. In the catacombs, lamps were used that hung from ropes or chains. Some lamps used vegetable oil, others animal fat (such as sheep or beef fat). The latter gave more light but was more expensive and smelled less pleasant. In any case, the lamps with liquid fuel depended on the amount of fuel and the thickness of the wick.

Of course, oil lamps were practically indispensable for finding your way in the dark. However, the decorations often seem to symbolize a deeper meaning. The Romans had an animistic worldview based on cosmic reciprocity. For them, it was important to make offerings to the gods, the emperor, and household gods like the lares. It is no coincidence that Roman oil lamps can have depictions of gods, while Catholics still light candles for loved ones. Fire burns and rises just like incense and perfume to the heavens. Thus, an oil lamp can be seen as a small form of offering, which both mortals and the eternal gods enjoy. 

Oil lamps were also used on the lararium, it was customary during worship at the house altar to light oil lamps. Thus, oil lamps form one of the many expressions of the Roman dharmic worldview in which the natural and supernatural were intertwined. During the introduction of Christianity, this tradition was adopted by Christians, who depicted their own symbolism on the oil lamps. 

Research on lamps shows that hazelnut and walnut oil could also have been used. In parts of the empire where olive oil was not available, it had to be imported, making it expensive. In Germany, around Trier, the use of lamps varied greatly; more than 2700 ceramic lamps have been found there alone, while all of Great Britain has yielded only about 2600 lamps. This difference is likely related to how often and for what purposes lamps were used. In Great Britain, lamps were mainly used by the military and primarily in urban areas, but the total number remained small: in some places, only 100 have been found.

Earthenware lamps were not glazed, so they were likely treated with wax or resin to prevent oil from leaking easily. Bronze lamps, which were more expensive, did not require this. 

Lighting with candles and lamps has always been dangerous. In the nineteenth century, most fires in London were started by people working with candles. In Roman times, it was no different. There was a lot of flammable material in homes: wooden furniture, fabric curtains, and especially open flames.

One of the causes of fires in Roman houses was the spilling of oil. According to the law, people who were too careless with fire had to leave their homes. ("Whoever was careless with fire was not allowed to live there" – Digest 43.24.15).

Neighbors often helped to extinguish fires. Firefighters as we know them today did not exist. Sometimes the emperor sent a group of soldiers to help, but often ordinary people had to fight fires together.

When a major fire broke out in the city of Nicomedia, people requested permission to establish a firefighting group, but the emperor feared such a group would become a political club. He thought it better for people to work together in extinguishing fires without forming an official group.

Individual homeowners or residents had to have their own firefighting materials at home. The city watch of Rome had to ensure that people had a water supply in an upper room in case a fire broke out.

The law stipulated that houses had to be equipped with items to function properly – and this included firefighting materials. These items consisted of vinegar (to extinguish fires), cloths, buckets, sponges, fire hooks, and brushes. (Digest 33.7.12.16–8)