Roman technology is the collection of techniques, skills, methods, processes, and engineering practices which supported Roman civilization and made possible the expansion of the economy and military of ancient Rome (753 BC – 476 AD).
The Roman Empire was one of the most technologically advanced civilizations of antiquity, with some of the more advanced concepts and inventions forgotten during the turbulent eras of Late Antiquity and the early Middle Ages. Gradually, some of the technological feats of the Romans were rediscovered and/or improved upon during the Middle Ages and the beginning of the Modern Era; with some in areas such as civil engineering, construction materials, transport technology, and certain inventions such as the mechanical reaper, not improved upon until the 19th century. The Romans achieved high levels of technology in large part because they borrowed technologies from the Greeks, Etruscans, Celts, and others.
All technology uses energy to transform the material into a desirable object or uses some form of mechanics combined with another form to make something better. The cheaper energy is, the wider the class of technologies that are considered economic. This is why technological history can be seen as a succession of ages defined by energy type i.e. human, animal, water, peat, coal, and oil. The Romans used water power, and watermills were common throughout the Empire, especially to the end of the 1st century AD. They were used for cereals milling, sawing timber and crushing ore. They exploited wood and coal for heating. There were huge reserves of wood, peat and coal in the Roman Empire, but they were all in the wrong place. Wood could be floated down rivers to the major urban centres but otherwise it was a very poor fuel, being heavy for its caloric value. If this was improved by being processed into charcoal, it was bulky. Nor was wood ever available in any concentration. Diocletian's Price Edict can give us a glimpse of the economics of transporting wood. The maximum price of a wagon load of 1,200 lbs of wood was 150 d.(denari). The maximum freight charge per mile for the same wagon load was 20 d. per mile. Room heating was normally better done by charcoal braziers than hypocausts. But hypocausts did allow them to exploit any poor-quality smoky fuels like straw, vine prunings and small wood locally available. Hypocausts also allowed them to generate a humid heat for their baths.
The Romans worked almost all the coalfields of England that outcropped on the surface, by the end of the 2nd century (Smith 1997; 323). But there is no evidence that this exploitation was on any scale. After c. 200 AD the commercial heart of the Empire was in Africa and the East where the climate severely limited timber growth. There was no large coalfield on the edge of the Mediterranean.
With the crank and connecting rod system, all elements for constructing a steam engine (invented in 1712) — Hero's aeolipile (generating steam power), the cylinder and piston (in metal force pumps), non-return valves (in water pumps), gearing (in water mills and clocks) — were known in Roman times.
However, the aeolipile was a reaction engine, inefficient as a stationary engine. The first useful steam engine did not use steam pressure at all, but followed up a scientific advance in understanding air pressure.
Roman technology was largely based on a system of crafts, although the term engineering is used today to describe the technical feats of the Romans. The Greek words used were mechanic or machine-maker or even mathematician which had a much wider meaning than now. There were a large number of engineers employed by the army. The most famous engineer of this period was the Greek Apollodorus of Damascus. Normally each trade, each group of artisans—stonemasons, glass blowers, surveyors, etc.—within a project had its own practice of masters and apprentices, and many tried to keep their trade secrets, passing them on solely by word of mouth, a system still in use today by those who do not want to patent their inventions. Writers such as Vitruvius, Pliny the Elder and Frontinus published widely on many different technologies, and there was a corpus of manuals on basic mathematics and science such as the many books by Archimedes, Ctesibius, Heron (a.k.a. Hero of Alexandria), Euclid and so on. Not all of the manuals which were available to the Romans have survived, as lost works illustrate.
Much of what is known of Roman technology comes indirectly from archaeology and from the third-hand accounts of Latin texts copied from Arabic texts, which were in turn copied from the Greek texts of scholars such as Hero of Alexandria or contemporary travellers who had observed Roman technologies in action. Writers like Pliny the Elder and Strabo had enough intellectual curiosity to make note of the inventions they saw during their travels, although their typically brief descriptions often arouse discussion as to their precise meaning. On the other hand, Pliny is perfectly clear when describing gold mining, his text in book XXXIII having been confirmed by archaeology and field-work at such sites as Las Medulas and Dolaucothi.
The Romans made extensive use of aqueducts, dams, bridges, and amphitheatres. They were also responsible for many innovations to roads, sanitation, and construction in general. Roman architecture in general was greatly influenced by the Greeks and Etruscans. Many of the columns and arches seen in Roman architecture were adopted from the Greek and Etruscan civilizations present in Italy.
In the Roman Empire, cements made from pozzolanic ash/pozzolana and an aggregate made from pumice were used to make a concrete very similar to modern Portland cement concrete. In 20s BC the architect Vitruvius described a low-water-content method for mixing concrete. The Romans found out that insulated glazing (or "double glazing") improved greatly on keeping buildings warm, and this technique was used in the construction of public baths.
Another truly original process which was born in the empire was the practice of glassblowing, which started in Syria and spread in about one generation in the empire.
There were many types of presses to press olives. In the 1st century AD, Pliny the Elder reported the invention and subsequent general use of the new and more compact screw presses. However, the screw press was almost certainly not a Roman invention. It was first described by the Greek mathematician and engineer, Hero of Alexandria, but may have already been in use when he mentioned it in his Mechanica III.
Cranes were used for construction work and possibly to load and unload ships at their ports, although for the latter use there is according to the “present state of knowledge” still no evidence. Most cranes were capable of lifting about 6–7 tons of cargo, and according to a relief shown on Trajan's column were worked by treadwheel.
The Romans primarily built roads for their military. Their economic importance was probably also significant, although wagon traffic was often banned from the roads to preserve their military value. At its largest extent the total length of the Roman road network was 85,000 kilometres (53,000 mi).
Way stations providing refreshments were maintained by the government at regular intervals along the roads. A separate system of changing stations for official and private couriers was also maintained. This allowed a dispatch to travel a maximum of 800 kilometres (500 mi) in 24 hours by using a relay of horses.
The roads were constructed by digging a pit along the length of the intended course, often to bedrock. The pit was first filled with rocks, gravel or sand and then a layer of concrete. Finally they were paved with polygonal rock slabs. Roman roads are considered the most advanced roads built until the early 19th century. Bridges were constructed over waterways. The roads were resistant to floods and other environmental hazards. After the fall of the Roman Empire the roads were still usable and used for more than 1000 years.
Most Roman cities were shaped like a square. There were 4 main roads leading to the center of the city, or forum. They formed a cross shape, and each point on the edge of the cross was a gateway into the city. Connecting to these main roads were smaller roads, the streets where people lived.
The Romans constructed numerous aqueducts to supply water. The city of Rome itself was supplied by eleven aqueducts made of limestone that provided the city with over 1 million cubic metres of water each day, sufficient for 3.5 million people even in modern-day times, and with a combined length of 350 kilometres (220 mi).
Water inside the aqueducts depended entirely on gravity. The raised stone channels in which the water travelled were slightly slanted. The water was carried directly from mountain springs. After it had gone through the aqueduct, the water was collected in tanks and fed through pipes to fountains, toilets, etc.
The main aqueducts in Ancient Rome were the Aqua Claudia and the Aqua Marcia. Most aqueducts were constructed below the surface with only small portions above ground supported by arches. The longest Roman aqueduct, 178 kilometres (111 mi) in length, was traditionally assumed to be that which supplied the city of Carthage. The complex system built to supply Constantinople had its most distant supply drawn from over 120 km away along a sinuous route of more than 336 km.
Roman aqueducts were built to remarkably fine tolerances, and to a technological standard that was not to be equalled until modern times. Powered entirely by gravity, they transported very large amounts of water very efficiently. Sometimes, where depressions deeper than 50 metres had to be crossed, inverted siphons were used to force water uphill. An aqueduct also supplied water for the overshot wheels at Barbegal in Roman Gaul, a complex of water mills hailed as "the greatest known concentration of mechanical power in the ancient world".
Roman bridges were among the first large and lasting bridges built. They were built with stone and/or concrete and utilized the arch. Built in 142 BC, the Pons Aemilius, later named Ponte Rotto (broken bridge) is the oldest Roman stone bridge in Rome, Italy. The biggest Roman bridge was Trajan's bridge over the lower Danube, constructed by Apollodorus of Damascus, which remained for over a millennium the longest bridge to have been built both in terms of overall and span length. They were most of the time at least 60 feet (18 m) above the body of water.
An example of temporary military bridge construction is the two Caesar's Rhine bridges.
They also built many dams for water collection, such as the Subiaco Dams, two of which fed Anio Novus, one of the largest aqueducts of Rome. They built 72 dams in just one country, Spain and many more are known across the Empire, some of which are still in use. At one site, Montefurado in Galicia, they appear to have built a dam across the river Sil to expose alluvial gold deposits in the bed of the river. The site is near the spectacular Roman gold mine of Las Medulas. Several earthen dams are known from Britain, including a well-preserved example from Roman Lanchester, Longovicium, where it may have been used in industrial-scale smithing or smelting, judging by the piles of slag found at this site in northern England. Tanks for holding water are also common along aqueduct systems, and numerous examples are known from just one site, the gold mines at Dolaucothi in west Wales. Masonry dams were common in North Africa for providing a reliable water supply from the wadis behind many settlements.
The Romans also made great use of aqueducts in their extensive mining operations across the empire, some sites such as Las Medulas in north-west Spain having at least 7 major channels entering the minehead. Other sites such as Dolaucothi in south Wales was fed by at least 5 leats, all leading to reservoirs and tanks or cisterns high above the present opencast. The water was used for hydraulic mining, where streams or waves of water are released onto the hillside, first to reveal any gold-bearing ore, and then to work the ore itself. Rock debris could be sluiced away by hushing, and the water also used to douse fires created to break down the hard rock and veins, a method known as fire-setting.
Alluvial gold deposits could be worked and the gold extracted without needing to crush the ore. Washing tables were fitted below the tanks to collect the gold-dust and any nuggets present. Vein gold needed crushing, and they probably used crushing or stamp mills worked by water-wheels to comminute the hard ore before washing. Large quantities of water were also needed in deep mining to remove waste debris and power primitive machines, as well as for washing the crushed ore. Pliny the Elder provides a detailed description of gold mining in book xxxiii of his Naturalis Historia, most of which has been confirmed by archaeology. That they used water mills on a large scale elsewhere is attested by the flour mills at Barbegal in southern France, and on the Janiculum in Rome.
The Romans did not invent plumbing or toilets, but instead borrowed their waste disposal system from their neighbors, particularly the Minoans. A waste disposal system was not a new invention, but rather had been around since 3100 BCE, when one was created in the Indus River Valley  The Roman public baths, or thermae served hygienic, social and cultural functions. The baths contained three main facilities for bathing. After undressing in the apodyterium or changing room, Romans would proceed to the tepidarium or warm room. In the moderate dry heat of the tepidarium, some performed warm-up exercises and stretched while others oiled themselves or had slaves oil them. The tepidarium’s main purpose was to promote sweating to prepare for the next room, the caldarium or hot room. The caldarium, unlike the tepidarium, was extremely humid and hot. Temperatures in the caldarium could reach 40 degrees Celsius (104 degrees Fahrenheit). Many contained steam baths and a cold-water fountain known as the labrum. The last room was the frigidarium or cold room, which offered a cold bath for cooling off after the caldarium. The Romans also had flush toilets.
The Roman military technology ranged from personal equipment and armament to deadly siege engines. They inherited almost all ancient weapons.
While heavy, intricate armour was not uncommon (cataphracts), the Romans perfected a relatively light, full torso armour made of segmented plates (lorica segmentata). This segmented armour provided good protection for vital areas, but did not cover as much of the body as lorica hamata or chainmail. The lorica segmentata provided better protection, but the plate bands were expensive and difficult to produce and difficult to repair in the field. Overall, chainmail was cheaper, easier to produce, and simpler to maintain, was one-size fits all, and was more comfortable to wear – thus, it remained the primary form of armour even when lorica segmentata was in use.
The Roman cavalry saddle had four horns  and was believed to have been copied from Celtic peoples.
Roman siege engines such as ballistas, scorpions and onagers were not unique. But the Romans were probably the first people to put ballistas on carts for better mobility on campaigns. On the battlefield, it is thought that they were used to pick off enemy leaders. There is one account of the use of artillery in battle from Tacitus, Histories III,23:
In addition to innovations in land warfare, the Romans also developed the Corvus (boarding device) a movable bridge that could attach itself to an enemy ship and allow the Romans to board the enemy vessel. Developed during the First Punic War it allowed them to apply their experience in land warfare on the seas.
Rome was responsible for the innovation of other vital technology in addition to cataphracts, siege engines, and the Corvus.
In summary, Rome contributed numerous advances in technology to the Ancient World. However, it is also viewed that "the ancient world under the domination of Rome [in fact] reached a kind of climax in the technological field [as] many technologies had advanced as far as possible with the equipment then available". This concept of perfecting the unperfected was a theme that governed Roman technological supremacy throughout its 1,470 year reign. Ideas that had already been invented or designed: like the pontoon bridge, aqueduct, and military surgery, were constructed or utilized to perfection by Roman innovators. It's the innovation of technology that contributed to Rome's military success.
|Alum||The production of alum (KAl(SO4)2.12H2O) from alunite (KAl3(SO4)2.(OH)6) is archaeologically attested on the island Lesbos. This site was abandoned in the 7th century but dates back at least to the 2nd century AD.|
|Amphitheatre||See e.g. Colosseum.|
|Aqueduct, true arch||Pont du Gard, Segovia etc.|
|Bath, monumental public (Thermae)||See e.g. Baths of Diocletian|
|Book (Codex)||First mentioned by Martial in the 1st century AD. Held many advantages over the scroll.|
|Brass||The Romans had enough understanding of zinc to produce a brass denomination coinage; see sestertius.|
|Bridge, true arch||See e.g. Roman bridge in Chaves or the Severan Bridge.|
|Bridge, segmental arch||More than a dozen Roman bridges are known to feature segmental (=flat) arches. A prominent example was Trajan's bridge over the Danube, a lesser known the extant Limyra Bridge in Lycia|
|Bridge, pointed arch||Constructed in the early Byzantine era, the earliest known bridge featuring a pointed arch is the 5th or 6th century AD Karamagara Bridge|
|Camel harness||The harnessing of camels to ploughs is attested in North Africa by the 3rd century AD|
|Cameos||Probably a Hellenistic innovation e.g. Cup of the Ptolemies but taken up by the Emperors e.g. Gemma Augustea, Gemma Claudia etc.|
|Cast Iron||Recently archaeologically detected in the Val Gabbia in northern Lombardy from the 5th and 6th centuries AD. This technically interesting innovation appears to have had little economic impact. But archaeologists may have failed to recognize the distinctive slag, so the date and location of this innovation may be revised.|
|Crank handle||A Roman iron crank handle was excavated in Augusta Raurica, Switzerland. The 82.5 cm long piece with a 15 cm long handle is of yet unknown purpose and dates to no later than c. 250 AD.|
|Crank and connecting rod||Found in several water-powered saw mills dating from the late 3rd (Hierapolis sawmill) to 6th century AD (at Ephesus respectively Gerasa).|
|Dam, Arch||Currently best attested for the dam at Glanum, France dated c. 20 BC. The structure has entirely disappeared. Its existence attested from the cuts into the rock on either side to key in the dam wall, which was 14.7 metres high, 3.9m thick at base narrowing to 2.96m at the top. Earliest description of arch action in such types of dam by Procopius around 560 AD, the Dara Dam|
|Dam, Arch-gravity||Examples include curved dams at Orükaya, Çavdarhisar, both Turkey (and 2nd century)Kasserine Dam in Tunisia, and Puy Foradado Dam in Spain (2nd–3rd century)|
|Dam, Bridge||The Band-i-Kaisar, constructed by Roman prisoners of war in Shustar, Persia, in the 3rd century AD, featured a weir combined with an arch bridge, a multifunctional hydraulic structure which subsequently spread throughout Iran.|
|Dam, Buttress||Attested in a number of Roman dams in Spain, like the 600 m long Consuegra Dam|
|Dam, Multiple Arch Buttress||Esparragalejo Dam, Spain (1st century AD) earliest known|
|Dome, monumental||See e.g. Pantheon.|
|Foot-powered loom||Before 298 AD, with a hint the invention arose at Tarsus|
|Flos Salis||A product of salt evaporation ponds Dunaliella salina used in the perfume industry (Pliny Nat. Hist. 31,90)|
|Force pump used in fire engine||See image of pointable nozzle|
|Glass blowing||This led to a number of innovations in the use of glass. Window glass is attested at Pompeii in AD 79. In the 2nd century AD hanging glass oil lamps were introduced. These used floating wicks and by reducing self-shading gave more lumens in a downwards direction. Cage cups (see photograph) are hypothesised as oil lamps.|
|Dichroic glass as in the Lycurgus Cup.  Note, this material attests otherwise unknown chemistry (or other way?) to generate nano-scale gold-silver particles.|
|Glass mirrors (Pliny the Elder Naturalis Historia 33,130)|
|Greenhouse cold frames||(Pliny the Elder Naturalis Historia 19.64; Columella on Ag. 11.3.52)|
|Hydraulis||A water organ. Later also the pneumatic organ.|
|Hushing||Described by Pliny the Elder and confirmed at Dolaucothi and Las Médulas|
|Hydraulic mining||Described by Pliny the Elder and confirmed at Dolaucothi and Las Médulas|
|Hydrometer||Mentioned in a letter of Synesius|
|Hypocaust||A floor and also wall heating system. Described by Vitruvius|
|Lighthouses||The best surviving examples are those at Dover castle and the Tower of Hercules at A Coruña|
|Leather, Tanned||The preservation of skins with vegetable tannins was a pre-Roman invention but not of the antiquity once supposed. (Tawing was far more ancient.) The Romans were responsible for spreading this technology into areas where it was previously unknown such as Britain and Qasr Ibrim on the Nile. In both places this technology was lost when the Romans withdrew.|
|Mills||M.J.T.Lewis presents good evidence that water powered vertical pounding machines came in by the middle of the 1st century AD for fulling, grain hulling (Pliny Nat. Hist. 18,97) and ore crushing (archaeological evidence at Dolaucothi Gold Mines and Spain).|
|Grainmill, rotary. According to Moritz (p57) rotary grainmills were not known to the ancient Greeks but date from before 160 BC. Unlike reciprocating mills, rotary mills could be easily adapted to animal or water power. Lewis (1997) argues that the rotary grainmill dates to the 5th century BC in the western Mediterranean. Animal and water powered rotary mills came in the 3rd century BC.|
|Sawmill, water powered. Recorded by 370 AD. Attested in Ausonius's poem Mosella. Translated "the Ruwer sends mill-stones swiftly round to grind the corn, And drives shrill saw-blades through smooth marble blocks". Recent archaeological evidence from Phrygia, Anatolia, now pushes back the date to the 3rd century AD and confirms the use of a crank in the sawmill.|
|Shipmill, (though small, the conventional term is "shipmill" not boat mill, probably because there was always a deck, and usually an enclosed superstructure, to keep the flour away from the damp) where water wheels were attached to boats, was first recorded at Rome in 547 AD in Procopius of Caesarea's Gothic Wars (1.19.8–29) when Belisaurius was besieged there.|
|Essentials of the Steam engine||By the late 3rd century AD, all essential elements for constructing a steam engine were known by Roman engineers: steam power (in Hero's aeolipile), the crank and connecting rod mechanism (in the Hierapolis sawmill), the cylinder and piston (in metal force pumps), non-return valves (in water pumps) and gearing (in water mills and clocks)|
|Watermill. Improvements upon earlier models. For the largest mill complex known see Barbegal|
|Mercury Gilding||as in the Horses of San Marco|
|Newspaper, rudimentary||See Acta Diurna.|
|Paddle wheel boats||In de Rebus Bellicis (possibly only a paper invention).|
|Pewter||Mentioned by Pliny the Elder (Naturalis Historia 34, 160–1). Surviving examples are mainly Romano-British of the 3rd and 4th centuries e.g. and . Roman pewter had a wide range of proportions of tin but proportions of 50%, 75% and 95% predominate (Beagrie 1989).|
|Pleasure lake||An artificial reservoir, highly unusual in that it was meant for recreational rather than utilitarian purposes was created at Subiaco, Italy, for emperor Nero (54–68 AD). The dam remained the highest in the Roman Empire (50 m), and in the world until its destruction in 1305.|
|iron-bladed (A much older innovation (e.g. Bible; I Samuel 13, 20–1) that became much more common in the Roman period)|
|wheeled (Pliny the Elder Naturalis Historia 18. 171–3) (More important for the Middle Ages, than this era.)|
|Pottery, glossed||i.e. Samian ware|
|Reaper||An early harvesting machine: vallus (Pliny the Elder Naturalis Historia 18,296, Palladius 7.2.2–4 )|
|Sails, fore-and-aft rig||Introduction of fore-and-aft rigs 1) the Lateen sail 2) the Spritsail, this last already attested in 2nd century BC in the northern Aegean Sea Note: there is no evidence of any combination of fore-and-aft rigs with square sails on the same Roman ship.|
|Sails, Lateen||Representations show lateen sails in the Mediterranean as early as the 2nd century AD. Both the quadrilateral and the triangular type were employed.|
|Roller Bearings||Archaeologically attested in the Lake Nemi ships|
|Rudder, stern-mounted||See image for something very close to being a sternpost rudder|
|Sausage, fermented dry (probably)||See salami.|
|Screw press||An innovation of about the mid-1st century AD|
|Sewers||See for example Cloaca Maxima|
|Soap, hard (sodium)||First mentioned by Galen (earlier, potassium, soap being Celtic).|
|Spiral staircase||Though first attested as early as the 5th century BC in Greek Selinunte, spiral staircases only become more widespread after their adoption in Trajan's column and the Column of Marcus Aurelius.|
|Stenography, a system of||See Tironian notes.|
|Street map, early||See Forma Urbis Romae (Severan Marble Plan), a carved marble ground plan of every architectural feature in ancient Rome.|
|Sundial, portable||See Theodosius of Bithynia|
|Surgical instruments, various|
|Tooth implants, iron||See |
|Towpath||e.g. beside the Danube, see the "road" in Trajan's bridge|
|Tunnels||Excavated from both ends simultaneously. The longest known is the 5.6-kilometre (3.5 mi) drain of the Fucine lake|
|Vehicles, one wheeled||Solely attested by a Latin word in 4th century AD Scriptores Historiae Augustae Heliogabalus 29. As this is fiction, the evidence dates to its time of writing.|
|Wood veneer||Pliny Nat. Hist. 16. 231–2|
A bellows or pair of bellows is a device constructed to furnish a strong blast of air. The simplest type consists of a flexible bag comprising a pair of rigid boards with handles joined by flexible leather sides enclosing an approximately airtight cavity which can be expanded and contracted by operating the handles, and fitted with a valve allowing air to fill the cavity when expanded, and with a tube through which the air is forced out in a stream when the cavity is compressed. It has many applications, in particular blowing on a fire to supply it with air.
The term "bellows" is used by extension for a flexible bag whose volume can be changed by compression or expansion, but not used to deliver air. For example, the light-tight (but not airtight) bag allowing the distance between the lens and film of a folding photographic camera to be varied is called a bellows.Bookcase
A bookcase, or bookshelf, is a piece of furniture with horizontal shelves, often in a cabinet, used to store books or other printed materials. Bookcases are used in private homes, public and university libraries, offices and bookstores. Bookcases range from small, low models the height of a table to high models reaching up to ceiling height. Shelves may be fixed or adjustable to different positions in the case. In rooms entirely devoted to the storage of books, such as libraries, they may be permanently fixed to the walls and/or floor.
A bookcase may be fitted with glass doors that can be closed to protect the books from dust or moisture. Bookcase doors are almost always glazed with glass, so as to allow the spines of the books to be read. Especially valuable rare books may be kept in locked cases with wooden or glazed doors. A small bookshelf may also stand on some other piece of furniture such as a desk or chest. Larger books are more likely to be kept in horizontal piles and very large books flat on wide shelves or on coffee tables.
In Latin and Greek the idea of bookcase is represented by Bibliotheca and Bibliothēkē (Greek: βιβλιοθήκη), derivatives of which mean library in many modern languages. A bookcase is also known as a bookshelf, a bookstand, a cupboard and a bookrack. In a library, large bookshelves are called "stacks."Cameo (carving)
Cameo () is a method of carving an object such as an engraved gem, item of jewellery or vessel. It nearly always features a raised (positive) relief image; contrast with intaglio, which has a negative image. Originally, and still in discussing historical work, cameo only referred to works where the relief image was of a contrasting colour to the background; this was achieved by carefully carving a piece of material with a flat plane where two contrasting colours met, removing all the first colour except for the image to leave a contrasting background.
A variation of a carved cameo is a cameo incrustation (or sulphide). An artist, usually an engraver, carves a small portrait, then makes a cast from the carving, from which a ceramic type cameo is produced. This is then encased in a glass object, often a paperweight. These are very difficult to make but were popular from the late 18th century through the end of the 19th century. Originating in Bohemia, the finest examples were made by the French glassworks in the early to mid-nineteenth century.Today the term may be used very loosely for objects with no colour contrast, and other, metaphorical, terms have developed, such as cameo appearance. This derives from another generalized meaning that has developed, the cameo as an image of a head in an oval frame in any medium, such as a photograph.Chain pump
The chain pump is type of a water pump in which several circular discs are positioned on an endless chain. One part of the chain dips into the water, and the chain runs through a tube, slightly bigger than the diameter of the discs. As the chain is drawn up the tube, water becomes trapped between the discs and is lifted to and discharged at the top. Chain pumps were used for centuries in the ancient Middle East, Europe, China.Crank (mechanism)
A crank is an arm attached at a right angle to a rotating shaft by which reciprocating motion is imparted to or received from the shaft. It is used to convert circular motion into reciprocating motion, or vice versa. The arm may be a bent portion of the shaft, or a separate arm or disk attached to it. Attached to the end of the crank by a pivot is a rod, usually called a connecting rod (conrod). The end of the rod attached to the crank moves in a circular motion, while the other end is usually constrained to move in a linear sliding motion.
The term often refers to a human-powered crank which is used to manually turn an axle, as in a bicycle crankset or a brace and bit drill. In this case a person's arm or leg serves as the connecting rod, applying reciprocating force to the crank. There is usually a bar perpendicular to the other end of the arm, often with a freely rotatable handle or pedal attached.Crankshaft
A crankshaft—related to crank—is a mechanical part able to perform a conversion between reciprocating motion and rotational motion. In a reciprocating engine, it translates reciprocating motion of the piston into rotational motion; whereas in a reciprocating compressor, it converts the rotational motion into reciprocating motion. In order to do the conversion between two motions, the crankshaft has "crank throws" or "crankpins", additional bearing surfaces whose axis is offset from that of the crank, to which the "big ends" of the connecting rods from each cylinder attach.
It is typically connected to a flywheel to reduce the pulsation characteristic of the four-stroke cycle, and sometimes a torsional or vibrational damper at the opposite end, to reduce the torsional vibrations often caused along the length of the crankshaft by the cylinders farthest from the output end acting on the torsional elasticity of the metal.De architectura
De architectura (On architecture, published as Ten Books on Architecture) is a treatise on architecture written by the Roman architect and military engineer Marcus Vitruvius Pollio and dedicated to his patron, the emperor Caesar Augustus, as a guide for building projects. As the only treatise on architecture to survive from antiquity, it has been regarded since the Renaissance as the first book on architectural theory, as well as a major source on the canon of classical architecture. It contains a variety of information on Greek and Roman buildings, as well as prescriptions for the planning and design of military camps, cities, and structures both large (aqueducts, buildings, baths, harbours) and small (machines, measuring devices, instruments). Since Vitruvius published before the development of cross vaulting, domes, concrete, and other innovations associated with Imperial Roman architecture, his ten books are not regarded as a source of information on these hallmarks of Roman building design and technology.Fork
In cutlery or kitchenware, a fork (from the Latin furca ("pitchfork")) is a utensil, now usually made of metal, whose long handle terminates in a head that branches into several narrow and often slightly curved tines with which one can spear foods either to hold them to cut with a knife or to lift them to the mouth.Gimbal
A gimbal is a pivoted support that allows the rotation of an object about a single axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of the rotation of its support (e.g. vertical in the first animation). For example, on a ship, the gyroscopes, shipboard compasses, stoves, and even drink holders typically use gimbals to keep them upright with respect to the horizon despite the ship's pitching and rolling.
The gimbal suspension used for mounting compasses and the like is sometimes called a Cardan suspension after Italian mathematician and physicist Gerolamo Cardano (1501–1576) described it in detail. However, Cardano did not invent the gimbal, nor did he claim to. The device has been known since antiquity, first described in the 3rd c. BC by Philo of Byzantium, although some modern authors support it may not have a single identifiable inventor.Hydrometer
A hydrometer is an instrument used for measuring the relative density of liquids based on the concept of buoyancy. They are typically calibrated and graduated with one or more scales such as specific gravity.
A hydrometer usually consists of a sealed hollow glass tube with a wider bottom portion for buoyancy, a ballast such as lead or mercury for stability, and a narrow stem with graduations for measuring. The liquid to test is poured into a tall container, often a graduated cylinder, and the hydrometer is gently lowered into the liquid until it floats freely. The point at which the surface of the liquid touches the stem of the hydrometer correlates to relative density. Hydrometers can contain any number of scales along the stem corresponding to properties correlating to the density.
Hydrometers are calibrated for different uses, such as a lactometer for measuring the density (creaminess) of milk, a saccharometer for measuring the density of sugar in a liquid, or an alcoholometer for measuring higher levels of alcohol in spirits.
The hydrometer makes use of Archimedes' principle: a solid suspended in a fluid is buoyed by a force equal to the weight of the fluid displaced by the submerged part of the suspended solid. The lower the density of the fluid, the deeper a hydrometer of a given weight sinks; the stem is calibrated to give a numerical reading.List of Byzantine inventions
This is a list of Byzantine inventions. The Byzantine or Eastern Roman Empire represented the continuation of the Roman Empire after a part of it collapsed. Its main characteristics were Roman state traditions, Greek culture and Christian faith.Pig iron
Pig iron is an intermediate product of the iron industry, also known as crude iron, which is first obtained from a smelting furnace in the form of oblong blocks. Pig iron has a very high carbon content, typically 3.8–4.7%, along with silica and other constituents of dross, which makes it very brittle and not useful directly as a material except for limited applications. Pig iron is made by smelting iron ore into a transportable ingot of impure high carbon-content iron in a blast furnace as an ingredient for further processing steps. The traditional shape of the molds used for pig iron ingots was a branching structure formed in sand, with many individual ingots at right angles to a central channel or runner, resembling a litter of piglets being suckled by a sow. When the metal had cooled and hardened, the smaller ingots (the pigs) were simply broken from the runner (the sow), hence the name pig iron. As pig iron is intended for remelting, the uneven size of the ingots and the inclusion of small amounts of sand caused only insignificant problems considering the ease of casting and handling them.Roman abacus
The Ancient Romans developed the Roman hand abacus, a portable, but less capable, base-10 version of earlier abacuses like those used by the Greeks and Babylonians. It was the first portable calculating device for engineers, merchants and presumably tax collectors. It greatly reduced the time needed to perform the basic operations of arithmetic using Roman numerals.
As Karl Menninger says on page 315 of his book, "For more extensive and complicated calculations, such as those involved in Roman land surveys, there was, in addition to the hand abacus, a true reckoning board with unattached counters or pebbles. The Etruscan cameo and the Greek predecessors, such as the Salamis Tablet and the Darius Vase, gives us a good idea of what it must have been like, although no actual specimens of the true Roman counting board are known to be extant. But language, the most reliable and conservative guardian of a past culture, has come to our rescue once more. Above all, it has preserved the fact of the unattached counters so faithfully that we can discern this more clearly than if we possessed an actual counting board. What the Greeks called psephoi, the Romans called calculi. The Latin word calx means 'pebble' or 'gravel stone'; calculi are thus little stones (used as counters)."
Both the Roman abacus and the Chinese suanpan have been used since ancient times. With one bead above and four below the bar, the systematic configuration of the Roman abacus is coincident to the modern Japanese soroban, although the soroban is historically derived from the suanpan.Roman engineering
The ancient Romans were famous for their advanced engineering accomplishments, although some of their own inventions were improvements on older ideas, concepts and inventions. Technology for bringing running water into cities was developed in the east, but transformed by the Romans into a technology inconceivable in Greece. The architecture used in Rome was strongly influenced by Greek and Etruscan sources.
Roads were common at that time, but the Romans improved their design and perfected the construction to the extent that many of their roads are still in use today. Their accomplishments surpassed most other civilizations of their time, and after their time, and many of their structures have withstood the test of time to inspire others, especially during the Renaissance. Moreover, their contributions were described in some detail by authors such as Vitruvius, Frontinus and Pliny the Elder, so there is a printed record of their many inventions and achievements.Salt mining
A salt mine is a mine from which salt is extracted. The mined salt is usually in the form of halite (commonly known as rock salt), and extracted from evaporite formations.Sawmill
A sawmill or lumber mill is a facility where logs are cut into lumber. Modern saw mills use a motorized saw to cut logs lengthwise to make long pieces, and crosswise to length depending on standard or custom sizes (dimensional lumber). The "portable" saw mill is iconic and of simple operation—the logs lay flat on a steel bed and the motorized saw cuts the log horizontally along the length of the bed, by the operator manually pushing the saw. The most basic kind of saw mill consists of a chainsaw and a customized jig ("Alaskan saw mill"), with similar horizontal operation.
Before the invention of the sawmill, boards were made in various manual ways, either rived (split) and planed, hewn, or more often hand sawn by two men with a whipsaw, one above and another in a saw pit below. The earliest known mechanical mill is the Hierapolis sawmill, a Roman water-powered stone mill at Hierapolis, Asia Minor dating back to the 3rd century AD. Other water-powered mills followed and by the 11th century they were widespread in Spain and North Africa, the Middle East and Central Asia, and in the next few centuries, spread across Europe. The circular motion of the wheel was converted to a reciprocating motion at the saw blade. Generally, only the saw was powered, and the logs had to be loaded and moved by hand. An early improvement was the development of a movable carriage, also water powered, to move the log steadily through the saw blade.
By the time of the Industrial Revolution in the 18th century, the circular saw blade had been invented, and with the development of steam power in the 19th century, a much greater degree of mechanisation was possible. Scrap lumber from the mill provided a source of fuel for firing the boiler. The arrival of railroads meant that logs could be transported to mills rather than mills being built besides navigable waterways. By 1900, the largest sawmill in the world was operated by the Atlantic Lumber Company in Georgetown, South Carolina, using logs floated down the Pee Dee River from the Appalachian Mountains. In the 20th century the introduction of electricity and high technology furthered this process, and now most sawmills are massive and expensive facilities in which most aspects of the work is computerized. Besides the sawn timber, use is made of all the by-products including sawdust, bark, woodchips, and wood pellets, creating a diverse offering of forest products.Steelmaking
Steelmaking is the process of producing steel from iron ore and/or scrap. In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon(most important impurity) are removed from the sourced iron, and alloying elements such as manganese, nickel, chromium, carbon and vanadium are added to produce different grades of steel. Limiting dissolved gases such as nitrogen and oxygen and entrained impurities (termed "inclusions") in the steel is also important to ensure the quality of the products cast from the liquid steel.Steelmaking has existed for millennia, but it was not commercialized on a massive scale until late 19th century. The ancient craft process of steelmaking was the crucible process. In the 1850s and 1860s, the Bessemer process and the Siemens-Martin process turned steelmaking into a heavy industry. Today there are two major commercial processes for making steel, namely basic oxygen steelmaking, which has liquid pig-iron from the blast furnace and scrap steel as the main feed materials, and electric arc furnace (EAF) steelmaking, which uses scrap steel or direct reduced iron (DRI) as the main feed materials. Oxygen steelmaking is fuelled predominantly by the exothermic nature of the reactions inside the vessel; in contrast, in EAF steelmaking, electrical energy is used to melt the solid scrap and/or DRI materials. In recent times, EAF steelmaking technology has evolved closer to oxygen steelmaking as more chemical energy is introduced into the process.Technological history of the Roman military
The technology history of the Roman military covers the development of and application of technologies for use in the armies and navies of Rome from the Roman Republic to the fall of the Western Roman Empire. The rise of Hellenism and the Roman Republic are generally seen as signalling the end of the Iron Age in the Mediterranean. Roman iron-working was enhanced by a process known as carburization. The Romans used the better properties in their armaments, and the 1,300 years of Roman military technology saw radical changes. The Roman armies of the early empire were much better equipped than early republican armies. Metals used for arms and armor primarily included iron, bronze, and brass. For construction, the army used wood, earth, and stone. The later use of concrete in architecture was widely mirrored in Roman military technology, especially in the application of a military workforce to civilian construction projects.Urn
An urn is a vase, often with a cover, that normally has a somewhat narrowed neck above a rounded body and a footed pedestal. Describing a vessel as an "urn", as opposed to a vase or other terms, generally reflects its use rather than any particular shape or origin. The term is especially often used for funerary urns, vessels used in burials, either to hold the cremated ashes or as grave goods, but is used in many other contexts; in catering large vessels for serving tea or coffee are often called "tea-urns", even when they are metal cylinders of purely functional design. Large sculpted vases are often called urns, whether placed outdoors, in gardens or as architectural ornaments on buildings, or kept inside.
Ancient Rome topics
|Lists and other|