热水器历史

古代早期浴场

热水浴的历史可以追溯到史前时期利用天然温泉，以及希腊人开发、罗马人完善的复杂的人工加热系统，并在西班牙（Hispania）等地保持着很强的延续性。

天然温泉在人工浴场出现之前很久就已在世界各地被利用。人工加热和专门建造的温泉设施则兴起于地中海古典时期。

Prehistoric and Natural Hot Springs (Worldwide)

Humans have used natural geothermal springs for bathing, healing, and rituals since Paleolithic times wherever they occurred.

There is no single “oldest” site, but evidence and traditions exist across continents:

Australia (Aboriginal Dreamtime associations with water sources).

China (early use of hot springs; the stone pool at Huaqing/Huaqing Chi associated with the Qin dynasty in the 3rd century BC is among the oldest documented constructed spa pools).

Japan (onsen tradition with possible deep antiquity, though specific early claims are speculative).

Mesoamerica, Anatolia (Hittites), and the Mediterranean.

In the Indus Valley, the Great Bath at Mohenjo-Daro (~2500 BC) was a large public water structure, though it appears more ritual than thermally heated.

Greek Baths

Greek bathing culture provides the direct precursor to Roman systems.

Literary references appear in Homer (8th century BC), where warm baths restore heroes.

Public baths (balaneia) are archaeologically attested from the mid-5th century BC (e.g., the Dipylon Baths in Athens). They typically featured circular rooms (tholoi) with individual hip-baths along the walls; bathers sat and had hot water poured over them rather than immersing in shared pools.

Water was heated by braziers, hot rocks, or early furnaces. Some Hellenistic examples (3rd–2nd centuries BC, such as at Gortys in Arcadia, Gela in Sicily, and later phases at Olympia) show elementary underfloor heating experiments that anticipate the hypocaust.

Baths were linked to gymnasia and healing sanctuaries (Asclepieia). Hippocrates (5th–4th century BC) discussed the properties of different waters and the effects of hot and cold baths.

Natural thermal springs (e.g., Loutraki near Corinth, Aedipsos) were used earlier and continued alongside artificial facilities.

Greek baths emphasized individual cleansing and were less monumental or socially central than later Roman ones.

罗马浴场和地下供暖系统

罗马人将沐浴变成了一种大众化的社交、卫生和娱乐活动，并将其推广到整个帝国。

起源：以希腊建筑为蓝本，融合了意大利当地的农业传统，并利用了坎帕尼亚地区（靠近巴亚和弗莱格瑞平原）的天然火山热能。伊特鲁里亚人早在公元前8至4世纪就已开始利用温泉。

早期公共浴场（balnea）：公元前3至2世纪出现在意大利中部。重要遗址包括弗雷杰莱（拉齐奥）——第一阶段（公元前3世纪晚期）展现出受希腊西部/西西里浴场影响的先进特征；第二阶段（公元前2世纪中期）包含已知最早的成熟“维特鲁威式”地暖系统之一（砖砌基座上的抬高式地面，使热空气在其下方循环）。庞贝的斯塔比亚浴场（公元前2世纪）也拥有早期地暖系统。

地暖系统（hypocaust，源自希腊语“下烧式”）：来自炉膛（praefurnium）的热空气流经悬空的地板下方，通常也通过墙壁上的烟道（tubuli）。古代作家（如普林尼等）认为商人塞尔吉乌斯·奥拉塔（约公元前80年）发明了“悬空浴池”（pensiles balineae），但考古发现表明这项技术比他早几十年甚至更久；奥拉塔很可能对其进行了改进和商业化（包括用于牡蛎养殖场和别墅）。维特鲁威在公元前15年左右详细描述了这套系统。

发展：到了罗马共和国晚期和帝国早期，浴场包括分级区域——更衣室（apodyterium）、冷水室（frigidarium）、温水室（tepidarium）和热水室（caldarium）——以及汗蒸室（laconica）、运动场（palaestrae），有时还设有图书馆或讲堂。大型皇家浴场始于罗马的阿格里帕浴场（公元前1世纪晚期），并在图拉真、卡拉卡拉和戴克里先等皇帝统治时期达到了惊人的规模。

社会角色：沐浴面向大多数阶层开放（通常免费或低价），成为一种集卫生、锻炼、交流和身份象征于一体的日常仪式。在帝国鼎盛时期，仅罗马一地就有数百个公共浴场。

西班牙（Hispania）与延续性

罗马浴场随着殖民化和军事扩张而出现。

早期例子：与殖民地建立有关，例如瓦伦西亚（公元前 138 年建立）和卢戈（公元前 15 年左右建于该城市建立附近，利用温泉）周围的地区。

著名景点：塔拉戈纳、埃梅里塔奥古斯塔（梅里达）、伊塔利卡、塞戈布里加等地均有遗址。位于拉阿尔库迪亚（埃尔切附近）的东部浴场是一座大型公元2世纪建筑群，内设令人印象深刻的游泳池（natatio）。

阿兰赫（位于梅里达附近的巴达霍斯）：因其持续或近乎持续的传统而具有重要意义。这些药用温泉浴场使用天然温水（约28摄氏度）。其建筑（包括两个圆形穹顶房间——一个供男性使用，一个供女性使用——以及中央水池）可追溯至公元2至3世纪（在图拉真和哈德良统治时期均有使用；一块奉献铭文证实了3世纪的活动）。在经历了衰落和废弃之后，浴场从18世纪末/19世纪初开始得到修复。罗马时期的房间至今仍与现代温泉浴场（阿兰赫温泉浴场）融为一体，使其成为西班牙保存最完好、使用时间最长的罗马温泉设施之一。它也是梅里达考古遗址群（联合国教科文组织世界遗产）的一部分。

后来，西哥特时期，尤其是伊斯兰时期，延续了这一传统。阿拉伯浴场（例如，10世纪哈卡姆二世统治时期科尔多瓦的巴尼奥斯·哈里法莱斯浴场）借鉴了罗马的地暖技术，用于蒸汽供暖和冷热交替的房间。许多西班牙地名（如卡尔达斯、阿尔哈马）都体现了温泉文化。

Roman Heating Technology in Detail

The Romans developed the most sophisticated ancient systems for both room heating and hot water.

Hypocaust (underfloor and wall heating): A furnace (praefurnium) burned wood (or sometimes charcoal).

Hot air and smoke flowed into a void under a raised floor (suspensura) supported by stacks of brick pillars (pilae, typically spaced about 60 cm apart and often taller or reinforced near walls and under pools). The floor surface usually consisted of large tiles (bipedales), concrete, and a finished top layer (marble, mosaic, or tile).

Floors often sloped gently toward the furnace so heat circulated efficiently. Exhaust gases rose through vertical flues in the walls—early systems used tegulae mammatae (tiles with protruding knobs creating air channels); later and more common were tubuli (hollow rectangular clay pipes stacked against the walls).

These heated the walls by radiation and convection, then vented through the roof. In some cases, heating extended into vaults.

Studies of well-preserved sites (e.g., Indirizzo Baths in Catania) suggest hypocaust gas temperatures of roughly 90–125°C (sometimes higher near the furnace), producing comfortable room temperatures in the caldarium of about 30–40°C while avoiding dangerously hot surfaces. Large complexes required continuous firing; cooling a major bath could take days, so fires often ran day and night. Fuel demands were high—some provincial baths are estimated to have required the equivalent of a hectare of managed woodland per year.

Hot-water boilers and pool heating: The same furnaces usually heated water. Large bronze or lead cauldrons (boilers) sat directly over or beside the fire, often insulated by masonry. Vitruvius describes a practical three-boiler arrangement for double (men’s/women’s) baths: one for hot water, one for tepid, and one for cold, interconnected so that as hot water was drawn, tepid water replaced it and cold water topped up the tepid tank. Cold water typically came from aqueducts or cisterns via lead pipes and valves.

A specialized device called the testudo alvei (“turtle of the pool”) helped keep the water in the hot plunge pools (alvei) warm. This was a semi-cylindrical metal container (bronze or copper) open at one end to the pool bottom and positioned so its flat base sat directly in the furnace heat. Water circulated by convection: cooler water sank into the testudo, heated, and rose back into the pool. Evidence appears as early as the Stabian Baths in Pompeii; metal components were often later scavenged, so archaeological traces can be incomplete. Some pools also benefited from the radiant heat of the hypocaust floor beneath them.

Service areas for the stokers (often slaves) were practical and separated from the public spaces. Window glass, introduced more widely in the 1st century AD, improved lighting and heat retention in the hot rooms.

Greek and Early Systems

Greek public baths (balaneia) primarily used individual hip-baths with hot water poured over the bather. Heating was simpler—portable braziers, hot rocks, or small furnaces adjacent to the rooms. Some Hellenistic examples (3rd–2nd centuries BC in Sicily, southern Italy, and mainland Greece, such as Gortys and later phases at Olympia) show early channel or rudimentary underfloor heating that influenced Roman developments. Full Roman-style hypocausts and shared pools appear later in the Italian context.

Other Regions

Egypt: Private bathrooms with stone floors, drainage, and water-pouring arrangements exist from the Middle Kingdom onward in elite residences. Public baths of Greek (tholos/hip-bath) type arrived under the Ptolemies (Hellenistic period). Roman and Romano-Byzantine baths followed, with many well-preserved examples across the Nile Delta, oases, and sites such as Karnak, Trimithis, and Alexandria (including circular Ptolemaic public baths). Local adaptations persisted.

Near East and Mesopotamia: Pre-Hellenistic evidence is limited mainly to elite private bathtubs or simple pouring platforms. Public heated baths became more common after Greek and especially Roman influence. Later Byzantine and early Islamic baths (precursors to hammams) adapted hypocaust and steam techniques.

Elsewhere, Scythian-style sweat baths (felt tents with heated stones) are described by Herodotus. Pre-Islamic Iran had some public baths despite Zoroastrian concerns about polluting water; Sasanian rulers later promoted them. Chinese and Japanese thermal traditions focused more on natural hot springs, with constructed pools appearing by the Qin period in China.