CHANGES IN TOILET FEATURES

Paleolithic Age to Jomon Period: Disposal of Excrement by Natural Dissolution

It is thought that Paleolithic people were basically migratory, never staying in one place for a long time. In contrast, the remains of the dwellings of many settlements in the later Jomon Period form a horseshoe-shaped configuration, of which the center part was a plaza and where shell middens and garbage yards were formed outside the dwellings. This indicates an increasing tendency to sedentary settlement at that time. Actual fecal remains, known as coprolites, were found in the shell middens belonging to the Jomon Period. The coprolites were formed when the first the Jomon people or their housedogs defecated onto a shell midden.The excrement was subsequently covered by discarded shells. The coprolites naturally adhered to the shells in such a way as to maintain the original shapes of the excretions. Calcium seeped out of the shells and permeated the coprolites. As a result, the coprolites hardened to become stone-like. Because of this calcified condition, it was impossible to soften them by using trisodium phosphate. The late Michiko Chiura of the International Christian University, who once studied in Canada, endeavored to further our knowledge through studies of coprolites from the Torihama shell midden in Fukui Prefecture in 1970's. Regrettably the high hopes that accorded her as a pioneer of Japanese coprolite study were sadly lost when she passed away at the tragically young age of 35 in 1982. With her death, Japanese coprolite study lost its most dedicated researcher and no successors appeared for a long time. Still, the find of coprolites from shell middens, which were garbage dumps, suggests that people defecated at dumps outside dwellings or at places a little removed from the settlement, leaving the night soil subject only to the natural action of insects and plants. It seems that such a natural state of sanitation was sufficient during the Jomon Period which tended to have a modest populations with seasonal divisions of the populations or migrations. Such transhumance reduced serious environmental pollution. Conceivably people used the shell middens and garbage yards as toilets until this period, and they did not have any particular problems in doing so.

Despite the detection of many whipworm eggs by Kanehara and Kanehara (1995) in their analysis of the sediments of the lower creek within the San-nai Maruyama Site, Aomori Prefecture, they did not find roundworm eggs. This site is dated from Early and Middle Jomon, that is 6,000-3,500 BP and is famous for its extraordinary size and artifact richness. This research reinforces the credibility of the theory that many whipworms existed since the Jomon Period but no roundworm did, and that the prevalence of roundworm occurred after the Yayoi Period with the beginning of rice agriculture (Kanehara & Kanehara 1995).

The Yayoi Period to the Kofun (Burial Mound) Period and Later: Use of Moats as Toilets

The settlements of the Yayoi Period came to have a much greater population than ever before. As a result, many people had to live together within the confines of a limited amount of space all the year round. With regard to settlements in low lying land at the very least, it has been established that they were encircled by a moat and divided into several areas including a residential area, storage buildings, sacred area, and burial area. The existence of toilets, however, has not been firmly established. Nonetheless, the scientific analysis of the sediment obtained from moats encircling the Yayoi settlements has revealed the interesting facts that follow.

Coprophilous insects (Dung beetles) (Fig. 13) such as Onthophagus and Aphodius were found with aquatic insects including dytiscids in the moat encircling the Ikegami-Sone Site, Izumi City, Osaka Prefecture and excrement was left alongside the moat. This led Kanazawa and Miyatake (1990) of the Osaka City Museum of Natural History to conjecture that these moats once had a structure to allow excrement to be washed away when the water level rose due to rainfall etc. Also, parasite eggs of roundworm and whipworm were found in the sediment, suggesting that a moat encircling a settlement, previously thought to be only a military defensive feature, actually fulfilled the role of drainage as well. It is conceivable that the increase in population and the tendency to settle permanently in one location caused environmental pollution, making it necessary to improve the water supply and drainage. People dug wells in their settlements to obtain potable water, and discharged domestic wastewater and excrement into a channel or moat encircling the settlement. The old appellation for toilet in the Japanese language is "Kawa-ya", the sound of which may phonically remind us of two Chinese characters: i.e., "river-house". Supposedly, this is a derivation of the word for toilet. Roundworms and whipworms are typical parasites in this period, from which the conclusion can be drawn that the profile typical of human parasites in Japan up until the present day already existed at this time.

Meanwhile, the seeds and pollen grains of medicinal plants such as amaranth (Fig. 14), Chenopodium (Fig. 15), goosefoot, and others were detected in the ditch soil of the Ikegami-Sone Site and other large Yayoi settlements. These weed seeds had been commonly recovered from many Yayoi sites, although they had been thought as natural flora around the sites. This strengthened the possibility that these herbs, which had been regarded as mere weeds in the past, were actually medicinal herbs that ancient people used actively in treating themselves.

Kofun (Mounded Tomb) Period: Complete Toilet at the Makimuku Site

Not long after the toilet of the Fujiwara Palace Site was identified, Masaaki Kanehara found large amounts of fecal sediments and parasite eggs in the soil of a wooden conduit, usually referred to as a `water arrangement system' in the Makimuku Site at Sakurai City, Nara Prefecture. This was dated during the early third century AD. These features were regarded as representative of remains of ritual practice from the Kofun Period. Incidentally, similar features were found in several sites belonging to a period extending from the Kofun Period to the Nara Period(8th AD). Every report pertaining to these remains concludes that they are features of buildings used for some sort of ritual that made use of clean water.

Parasitological studies present an alternative interpretation. It is probable that these features were toilets, supported by the detection of large numbers of parasite eggs and undigested food residue in the soil samples made by Masaaki Kanehara. These samples had been collected for pollen analysis during an excavation of the Makimuku Site carried out by the Board of Education of Sakurai City. He checked it again after his finding of parasite eggs from the archaeological soil sample. Results of the analysis indicated that large quantities of parasite eggs were detected in the soil accumulated in the wooden conduit only, which leads to the conclusion that the wooden conduit remains were in fact part of a toilet structure. Consequently, features like this that have previously been designated as "water arrangement systems" or "remains of ritual structures" in the past are in fact more likely to have been toilets. However, based on the fact that ritual items including Komochi-Magatama (a comma-shaped bead with several smaller curved beads attached) were found beneath the coping surrounding those features, some opinion still favors the theory that these remains belong to ritual practice. Nonetheless, the authors favor the toilet hypothesis as the more logical of the two. If we accept the hypothesis that they are toilet features, then it must have been an advanced flushing-style toilet which filtered debris like leaves at a water intake port, and stored the water in a reservoir to supply it to another wooden conduit. A function of a collection tank is to provide water whenever required to facilitate flushing using vessels such as ladles or tubs. Water overflow is designed to pour over a low lip at the lower portion of the tank and onwards downstream. At a place immediately downstream next to the collection tank, "foothold"-like stones were found arranged. It is probable that this spot, arranged with stones below the outlet of the collection tank, is a place for excretion, from which excrement was washed away with water downstream through the wooden conduit.

A large amount of lung fluke (Paragonimus spp.) eggs in the soil were found in this location, the prevalence of which was possibly caused by the ingestion of too many river crabs. In addition, the findings of large amounts of safflower pollen combined with the fact that safflower (Carthamus tintorius L.) pollen was widely used as a raw material for parasiticides suggests that people took it as a medicine. This is also seen in the prescription in the ancient record.

Appearance of the Cesspit Type Toilet

The first cesspit found at 1-bo (ward), Ukyo 7th street in the Fujiwara Capital is sized 1.6 m in length, 0.5 m in width, and the depth of the pit is 0.4 m from the present surface. Considering the extensive excision and smoothening of old topsoil by agriculture, it is conceivable that the original depth in those days was 1.5 m or deeper (Figs 16, 17; Kurosaky 1992). Notwithstanding the fact that cesspit type toilets like this were found at the Koro-Kan of the 8th century in Dazaifu, Fukuoka City, the Yatate-demorithed temple Site of the 12th century in Odate City, Akita Prefecture, and the Yanagi-no-gosho Site of the 12th century (also) in Hiraizumi Town, Iwate Prefecture, the Fujiwara Capital was the first case in which contents were examined in detail. In the past, the decisive factors in identifying toilets were fly maggots and flat sticks called "chu-gi" used as a toilet paper. Preservation of such artifacts, however, requires an environment typically found in the wetland sites where a great number of organic remains, which would not be preserved at ordinary dry sites, can survive because they are protected by underground water. Every site does not have such an environment. There is no environment in the Japanese climate, which could preserve these organic remains other than the wetland sites that are constantly soaked with groundwater. This explains why toilet discoveries are so few in Japan.

Flushing Toilets in Cities

Subsequent to the discovery of a cesspit type toilet at the Fujiwara Capital, Matsui rediscovered the existence of a sort of flushing type toilet, which takes in water from a side gutter alongside the main streets of the capital and then discharges it, based on the results of an excavation of a mansion house at 2-bo (ward) 5-tsubo (block), 2-jo (street) of the Nara Capital. This discovery started with the discovery of food residues and parasite eggs usually contained in excrement and pollen distinctive to ancient toilets in soil downstream of the side gutter by Masaaki Kanehara, springing from a re-examination of preparations that had been made for pollen analysis. Matsui (2001) immediately examined ambient features, and then found the remains of a structure that corresponds to that of an ancient toilet. It is a facility in which a weir is provided in a side gutter of the small column avenue of the East 2nd-bo (ward), a closed conduit is provided in the foundation of the tsuiji-wall (tempered-earth wall with a roof), and water outflows through a wooden conduit provided parallel with the tsuiji-wall. The extension part of this drainage is unknown, as it is located outside the excavation area. Excavating downstream, however, revealed no extension of this gutter, leading to the conjecture that water outflow from the conduit was recycled back into the side gutter again.

The authors hold that these features are highly likely to be those of a toilet, reviewing the descriptions of the Decrees of Council of Administration dated February 9, Ko-nin 6 (815) and Sai-ko 2 (855) (cited from "Ruiju-sandai-kaku (the Collected Supplementary Penal Codes through Three Generations", Vol. 16, November 4, Jokan 7). The contents of these two Decrees of Council of Administration are as follows: "(Currently) at government offices and noblemen's mansion houses, they bore the foundation of walls, or dam up side gutters in order to take in water. A competent authority shall be ordered to make a plan to repair them. However, it shall not be prohibited to take water into residence. Untreated discharge of fouled sewage to the outside of residences shall be prohibited. Therefore, every hole shall immediately be provided with a wooden conduit to let water run through it"(815)."Many of the residences facing a gutter had a sluice gate in order to intentionally dam up a flow. This leads to damage to the foundations of local walls, thence causing muddiness on streets"(855).

The scene envisaged above fits precisely with the details of the toilet with sewage, which was excavated at the 5-tsubo (block), 2-bo (ward), 2-jo (street), Nara Capital. How was the "fouled waste" discharged from the sewage? The following descriptions are found in "Ryo-no-shuge (Collected Interpretations of the Administrative Laws)" and "Engi-shiki (Legal Procedures of the Engi Era)": "Prisoners shall be directed to clean up sewage at the Palace and government offices as well as toilets of the east and west on the morning after a rainy night" (Ryo-no-shuge).

"The person sentenced to penal servitude shall be directed to carry out construction work of roads and bridges and other miscellaneous work. Furthermore, the government office shall direct prisoners to sweep out the outside of the Palace every six days, and clean up sewage in the Palace and the gutters of toilets on the day after a rainy day"("Engi-shiki", Vol. 29, the order of the Prison Office). The reason why cleaning took place "on the day after a rainy day" is that rainwater that fell on the previous day runs through the auxiliary gutters of the roads of the Capital. Supposedly, it indicates that drainage facilities were of sufficient quality to efficiently carry rainwater away from the upper to the lower reach of the Capital. It is already known that long and narrow toilet buildings were provided here and there on the side gutters, performing the role of "public conveniences". As with the rivers that supply water to gutters in the Nara Capital, the Saho River runs east and the Akishino River runs west of the Capital. Facing the northern Narayama Hills, the rise and fall of these two riverbeds was adjusted so that water could be efficiently delivered throughout the entire capital. One might say that the construction of ancient cities were the projects that laid down the blueprint for the treatment of domestic sewage, especially considering that the Nagaoka Capital in Kyoto Prefecture (784-794) and the Heian Capital (794-1868), which followed afterwards, were based on a similar city plan. If we accept the hypothesis that the side gutters in streets in ancient capitals and cities were indeed sanitary sewers to treat excrement and domestic wastewater, we then face an interesting fact about the Fujiwara Capital, the first capital of Japan. The Fujiwara Capital assumes a form such that the imperial palace is set up at the north of the capital in which the emperor is enshrined in the same way as other capitals. Taking a view of the water system of an entire capital, however, the Asuka River runs from southeast to northwest. This water system means a "backflow" structure of domestic wastewater of the lower classes to the residential areas of the upper classes. The authors surmise that the short 16 year history of the Fujiwara Capital was due to vital defects in the city plan such as this one (Matsui 2001).