Underground Space. Vol. 1, pp. 1-8. © Pergamon Press 1976. Printed in U.S.A.

The Architectural Underground

KENNETH LABS

Star Route, Mechanicsville, PA 18934

Underground space is a resource of great potential benefit which has been exploited in different parts of the world for thousands of years. While some cultures literally have lived an underground existence, others have yet to realize any of the benefits of subsurface use. This article is concerned with the use of underground space for architectural applica• tion, i.e., designed for the purpose of human habitation or occupance for the tasks of daily life.* Historical underground applications usually revolve around a few primary themes, which are the subject of Part I. The major emphasis of interest in the subsurface has shifted several times in the past few decades, during which a rich assortment of building types and forms has emerged. Part II will examine these modern forms and functions with the intention of summarizing our current state of practice.

PART I: HISTORICAL THEMES OF -dwelling and "cave-building." Many benefits DEVELOPMENT have been gained by subsurface construction, and these may be summarized as listed below. Introduction 1HE use of undergrounq space (U. G. S.) has a rich ENVIRONMENTAL and fascinating history which has yet to be docu• Thermal dampening of daily and seasonal mented in a comprehensive, scholarly manner. temperature fluctuations. Several themes and related benefits of subsurface Protection from tornadoes, dust storms, architectural construction can be identified which hurricanes, fire. possess a surprising relevance to our 20th century desires to lessen somewhat our dependence on Resource-related technology, and to seek a closer cooperation with the processes of nature. Self-supporting soil offers construction Undoubtedly the first inhabitants of underground opportunity. space were troglodytes, or cave-dwellers. While Absence of building materials. mankind is assumed to have abandoned the cave for geographic mobility and the greater expedience of ANTHROPOLOGICAL surface dwellings, have in fact enjoyed con• Provides camouflage and concealment. tinual human habitation since paleolithic times. Offers defensive advantage and shelter from Indeed , many of man's first architectural endeavors attack. were either modifications of, or artificially created , caves. It is no accident that men - and entire Ceremonial cultures - have not relinquished the practice of Rich in symbolic meanings. Religious connotations. *This article is an elaboration of a paper, "The Use of Earth-Covered Buildings through History," Experiential (perceptive qualities) . presented at the Conference on Alternatives in In cases where a single major benefit offers an Energy Conservation: The Use of Earth-Covered Buildings held at the Center for Energy Policy extreme advantage over surficial alternatives, it may Studies, University of Texas at Arlington, July be solely responsible for the development of the 1975. subsurface. Enduring architectural solutions usually 2 Kenneth Labs may be said to be "multivalent" i.e., being excavated rock is used to create walled forecourts characterized by many levels of problems, the and exterior sheds that present a rowhouse-like resolutions of which are coincident in a single facade to the common street. These cliff-side physical design. Most underground architectural dwellings offer refuge from the climate, and simul• developments exhibit a multiplicity of benefits taneously elevate the community above the level of which are mutually reinforcing. The numerous the valley plain which is subject to occasional benefits of subsurface construction are manifested violent flooding. (See Fig. 2) by the following examples which have proved successful in different regions of the world.

North Africa Matmata is a village located in the arid lowlands of southern Tunisia. A population of several thousand live in artifical caves tunneled into the sides of excavated crater-like courtyards that range in depth from 20 to 40 feet, and average 30 to 40 feet square. Access to individual dwellings is by FIG. 2. Cliff-cut (rock-face) dwellings; a composite means of these courtyards which are said to provide of Berber, Italian, Chinese, and Turkish unit forms. a community function, "... each neighborhood Exterior courtyards and out-buildings are common square services up to 100 inhabitants and becomes a in both Chinese and Berber examples. natural front yard, rear yard, and storage and LaNier also cites the incidence of subterranean community space." (Goldfinger) [1]. atrium houses built by Roman colonists at Bulla Regia in northern Tunisia during the second century

A.D. (See Fig. 3). This is of special interest in contrast to the foregoing discussion , for the colonists made use of imported materials and their own cultural tradition:

"Normal Roman peristyle houses, with marble colonnaded courtyards, fountains, and mosaic tiled floors were built below ground in pits which were covered over with earth except for a small central courtyard . At ground level were walled gardens which contained on entry pavilion pro• FIG . 1. Cluster-courtyard development at Matmata. viding access to the stairway down." (LaNier) [2] Some villages in the loess belt of China may follow a similar mode of local planning. (no scale)

Court areas are connected to the surface by sloping , off which are located chambers for storage and animal quarters. Dwellings lie beneath f4:Af• II 20-30 feet of earth, a superb" insulation from the 1 extreme heat and severe local windstorms. The . ...,.. ... consequent form - or more accurately, the lack thereof - produces an inconspicuous skyline that has been a protective aid from roving nomadic FIG. 3. At left: community pattern of individual bands of the past. family units surrounding courtyards (dotted) at Matm;lta's underground development is thought Seripe. At right: plan of atrium unit described by to be primarily a response to the harsh climate of LaNier at Bulla Regia. (after LaNier {2}, no scale) the desert. Two other factors contribute to the propriety of subsurface use, viz., the absence of Since the Romans supplied their own materials building materials and a geological opportunity of a and followed the conventional (Roman) practice of self-supporting sandstone. The additional "invisi• surface street development, it may be assumed that bility" to marauders makes the subterranean village their interest in the underground was entirely a superbly adapted to its cultural, as as physical, response to the climate of the North African Coast. environment. It is likely that the Romans learned this practice Near Matmata in southern Tunisia are commu• from the Berbers, although the colonists' adaptation nities of cliff-cut cave houses also constructed by departed from the Berbers' construction method. the Berbers. Royce LaNier describes these settle• ments as ranging in population from 500 to 7 ,000. Northern and Western China Habitable rooms are carved from limestone. The A similar atrium-style of development occurs The Architectural Underground 3

throughout the provinces of Honan, Shensi, Shansi, I Turkey and Kansu in northern and western China. An Perhaps best known of troglodyte worlds is the estimated 10 million inhabitants live in subsurface area of Cappadocia in Turkey , which is renowned dwellings carved out of the self-supporting soil of not only for its abundance of cliff-cut dwellings, China's loess belt. Here, too, a climatic advantage is but also for the existence of some 41 underground reported for the dwellings. Geographer George B. cities (See Giovannini [7] , Rudofsky [8] ). Because Cressey writes, Cappadocia is associated with the refuge of early Christians, it is often assumed that the underground I "Since the soil is unconsolidated, it is easy to dig settlements were defensive in origin.J The intentions cave-dwellings in it. These are cool in summer and com• fortable in winter. Where a high bank adjoins a cultivated of the first creators of troglodytic Cappadocia are in field, the farmer may dig tunnels for his home and fact unknown, but surely the physical context itself I literally live beneath his farm. Small shafts for smoke lead supplied sufficient cause and opportunity alike. The from stoves in the cave dwellings to the field above. Thus barren and eerie topography is evidence of the one may see smoke curling up from cultivated fields. No severe winters and desert-like summers which are I house is in sig ht , and only as one peers over the cliff can h e see the courtyard with its various cave entrances responsible for the paucity of normal building below. Such land does double duty, with dwellings below materials. These conditions, coupled with the and fields 'upstairs.'." (Cressey) [3] presence of easily-carved volcanic tuff , contributed to an overall mix of environmental and cultural The Chinese underground is poorly documented , but available sources indicate that it comprises the factors favoring subsurface development. (Hazer) [9]. three generic types indicated in Figs. 1, 2, and 3. Nowhere is this opportunity exploited more fully Courtyards appear to be intrinsic to all documented than in the underground cities of Cappadocia, "one schemes, although they may serve somewhat differ• of which, penetrated through a single entrance ent functions. Single-unit/single story courtyards extended over an area of six kilometers." (Kostof) (such as those depicted in Rudofsky 's popular Archi• [10]. Some of these cities consisted of 8-10 levels tecture Without Architects [4]) provide private and housed livestock, storage areas, wineries, , outdoor space for each dwelling, and are generally and living areas - all subterranean. Despite our independent of the common L-shaped access stair ignorance of the founding of these urban centers, which accompanies each unit. These atriums may be there is little question regarding their appropri• 30' to 40' square and are "shaped, sized, and ateness to the climate and geography of central oriented to permit penetration of the low winter Turkey. sun." (J. M. Fitch) [5]

Multi-story courtyards, in the mode of Matmata, Mediterranean serve several dwellings and cover approximately 1/8 Other troglodyte settlements are to be found acre with a depth of 25' to 30'. Andrew Boyd [6] throughout the Mediterranean coast of Europe and reports cliff-cut dwellings almost indistinguishable in the Near East. Among these are villages in Spain, plan from the Berber cave-houses; the courtyards at , Greece, Jordan, Israel, and Egypt (See [1], these multiple-level units frequently contain guest [2], [11]). Many of these are variations of cliff-cut rooms and a privy at ground level. caves and are a product of environmental circum• Like the Tunisian communities, the Chinese stances and resources such as those previously dis• examples demonstrate an effort to temper an cussed. For a more complete survey of troglodytic inhospitable climate - albeit one quite different sites, see LaNier's Geotecture [21. from that of North Africa. The thermal benefit realized in China is gained against the winter cold and its bitter winds, although this is not an exclu • Religious and Symbolic Aspects sive cause for exploiting the subsurfaces. The subsurface seemingly has always possessed religious and/or symbolic connotations. Prior to the Northern Ghana mythical underworld of Hades through Dante's Still ttnother courtyard pattern of development is Inferno and up to the contemporary underground found in the village of Seripe, a small community urban sculpture proposals of Somaini Crispolti, the which covers 20-30 acres just north of the Ivory subsurface has represented the unknown and the 1 Coast of West Africa. The dwellings of Seripe are hallowed, from which springs life, in which is laid I not fully underground; they are built of earth and the dead. Western religions generally identify the semi-recessed, which gives them much of the same underground with death and burial , yet many sects I character and thermal benefit of subsurface con• (including several centuries of Christians in various struction (See Fig. 3). Pedestrian circulation occurs parts of the globe) have exploited the "other• I across the structures' roofs , and access to individual worldliness" of the subsurface for worship and dwellings is achieved via a ladder in the respective ceremonial purposes. In some cases this practice has courtyards of each. been the result of persecution and need for secrecy, 4 Kenneth Labs for others, perhaps to capture a sense of time• wildly-fluctuating temperatures of the southwest, lessness and permanence . the Indian tribes that built them generally resided in Whatever the intent, underground and rock-cut either adobe or masonry surface dwellings. churches abound throughout Cappadocia (Kostof) themselves were lined with stone walls or plastered [10], India and Pakistan (Woodcock) [12], with clay over the earth. In either case, the form Ethiopia (Owen) [13], and other parts of the was traditional and deviated little from an evolving world. In those troglodytic areas there is some ceremonial standard. question as to whether underground sanctuaries possess a special significance of themselves, or Spatial Characteristics whether they reflect an overall cultural adaptation There is, of course, a profound difference be• to climate and resources. In the latter case, the tween underground structures which are excavated security of the womblike underground environment in self-supporting media and those which are built may enhance the more utilitarian function of up and subsequently covered. Rock-cut and hand• providing space for ritual or worship. dug troglodytic architecture (a practice the author Of all examples, possibly none is more intriguing has sometimes irreverently - but not disrespectfully than the subterranean Indian of the American - referred to as "troglotecture") is characterized by Southwest. It is generally thought that Kivas were a plasticity and three-dimensionality unequalled in ceremonial meeting rooms, and that their use was surface construction. Moreover, the internal process restricted to adult males of the community. Their of creating - as opposed to enclosing - space size ranges from 10-14 feet for old Kayenta "small" carries with it a personal , spontaneous freedom of kivas, to a maximum of 83' diameter for an Anasazi expression found in few of the "styles" of architec• "Great Kiva" found in southwestern Colorado . ture. Shape, depth, and construction particulars vary This individuality of process could enable a man from site to site , but the use of an external to create his own dwelling, or even an entire ventilating shaft is nearly universal. This feature is church, with an excavating tool , scaffolding (if particularly interesting for it demonstrates a simple necessary), and a means of removing the waste. It but ingenious device for promoting air circulation in has been estimated that a room of 2 ,000 to 3,000 the underground chamber. (See Fig. 4) cubic feet could be carved out of Cappadocian tuff by a single man in one month (Kostof) [10]. Due

to the relative unimportance of structure and loading in such a situation, no prior engineering skills or architectural training was required. For American readers, perhaps the most imme• diate example of the complexity and spatial fluidity of this mode of construction is the fantasyland created by Baldasare Forestiere in southern Cali• fornia. The Fresno Gardens cover seven acres with tunnels and sky-lit underground chambers graciously planted with citrus trees. (Sanoff [14] Architecture Plus [15]) Hand-excavated with a shovel and wheel• 0 2M barrow, Forestiere's dream was to complete a 5,000 square feet underground restaurant with an 800' long auto access . He died in 1946 before

realizing his ambition , but left over 90 rooms varying in depth from 10'-35' below the surface. The Fresno Gardens is a labor of love , and it represents far more than an economical means of creating shelter. It records Forestiere's joy and infatuation with the experience of living in the interface between the earth and the atmosphere .

Underground buildings created through the cut• FIG. 4. Plan of a small kiva as uncovered by and-cover process of construction have yet to archaeologists at Antelope Mesa in Northeast achieve the plasticity of form and space exhibited Arizona. The cross section is a probable reconstruc• by the more "primitive" types of excavation• tion illustrating the convective air circulation system. architecture. These primitive types may suggest a The subsurface location of the kiva may be model - or a purpose - to which we may aspire in assumed to have special ceremonial significance. applying modern technology to underground Although the kiva is remarkably well-adapted to the development. The Architectural Underground 5

immediate use for storage of fruits and vegetables. Themes and Forms Throughout the mid-Atlantic and New England The themes which lead to the selection of an coast , underground storage precluded the freezing of underground solution undeniably will contribute to produce in winter and assured prolonged keeping its final typology , but its formal resolution will during the warmer months of the year. · always be determined by a host of additional Cellars became important features of every home• factors. Harsh climatic conditions, for example, may stead , and took on a variety of forms. Root cellars suggest the overall appropriateness of subsurface were cut into earthen banks and covered with sod structures , but amount of precipitation, defensive leaving the entrance nearly at ground level for eas: requirements, and geological conditions will dictate of wheelbarrow access. (See Fig. 5) The the relative feasibility of cliff-cut and atrium modes configuration was of further benefit in that its of development. Other site-specific circumstances geometry was contrived to shed water. In contrast , (geographic location, topography, availability of ground cellars are truly subterranean, and are building materials) will be factors in the design of termed "wet" or "dry", dependent on whether or access, lighting, ventilation, and the nature of not they were built in conjunction with a spring or "undergroundness." Cultural information will con• well. Figure 6 depicts a wet cellar located on the tribute significant inputs at all levels of develop• author's family farm in southeastern Pennsylvania. ment, from decorative details to patterns of

community and neighborly relationships. Among the recurring themes of underground use, no two seem more salient than that of climate and the nature of the site itself. There is something of a paradox in the relationship between these factors which may help to explain the global distribution of underground settlements. Temperate climates are generally mild, and characterized by an abundance of building materials, and by a regularity of annual precipitation . These building materials (either timber or masonry) are in themselves ill-suited for under• ground construction due to their inability to keep soil-laden moisture out, and/or due to the effects of dampness on the materials themselves. This has made it virtually impossible to build underground structures suitable for habitation in temperate-zone soil environments - precisely where the opportunity is most favorable for surface development. In harsh f!;IG. 5. , onnecticut root cellars were frequently banked, or dug out of a hillside. Such an arrange • climates, such as deserts - those least desirable for ment kept the cellar dry for storage of vegetables human occupation - the advantage of the sub• and roots in hay-lined racks. surface is greatest; there , where materials are scarce, the earth may offer both superior refuge and a building material of itself. With the advent of 20th

century materials and waterproofing methods, underground structures for architectural application have become a practical alternative to surface buildings in both "soft" and "wet" soils. The temperate zone in a sense has become the frontier of underground architectural development. The

remainder of this paper will deal with the heritage of underground use in America , and modern move• ments in underground development.

The American Tradition

Because America was settled mostly by Northern I I Europeans, it is not surprising that its settlement !,....- ,1 lacked a tradition of underground living . Colonial ...... ,/ Americans did bring with them, however , an FIG. 6. A wet cellar found on the author's family acknowledgement of the thermal stability of soil farm m southeastern Pennsylvania. Projecting stone environments; and , although deemed unsuitable for corbels in the corners were used as shelf supports habitation , root and ground cellars were put into for storing fruits and root crops. 6 Kenneth Labs

On a typical day in July, surface air temperature excavated from a firm soil, and was characterized measured 23° C, while temperature in the cellar was by an in-situ roof as well as walls. recorded as 13° C. The use of root and ground cellars spread west• "Another way of making a dugout was made mandatory where the hill was not high enough to leave a natural roof ward with the pioneers, and soon found more or the ravine was too shallow so an artificial roof had to elaborate expression in new applications. Among be prepared. This was made by placing tree logs across these were wine cellars, such as the Stone Hill the top of the cavity , then a layer of brush, then coarse Winery in the old German settlement of Hermann, hay and lastly sod and dirt completed the cover. Through Missouri. Boasting of the country's "largest series of this the stovepipe protruded." (Barns) [ 17]

arched cellars," the winery was constructed in the In such cases, a built-up front wall was necessitated. side of a hill and is laced with peripheral skylights It was usually constructed of square-cut turf blocks which penetrate the earthen cover. The masonry in the manner of surface sod houses, including a vaults of Stone Hill Wine Cellars have seen continual window if glass was available. The favored exposure wine production and / or mushroom growing (during was toward the east. Prohibition) since their construction in the 1860's. Like the sodhouse, the dugout offered a dis tinct During this same time period the generic form of thermal advantage over frame houses, and was free the "dugout" was playing an important role in the of danger from prairie fires. One Nebraska pioneer's settling of the prairies of the midwest. When the wife wrote, "Our dugout was so warm that during sodbusters arrived, and, the blizzard of 1888 we sat in it and let the fire go out." (Welsch) [18]. Few settlers romanticized the "As settlement crept westward and timber became more scarce, the homesteader came to depend more and more earthen walls and prairie roofs , through which on soil and grass for homes. The typical prairie house was snakes and cattle were equally likely to emerge. made of sod or was dug out of the side of a hill or Nevertheless, the dugout was a sensible adaptation ravine." (Dick) [ 16] to the physical environment and was comfortable, though not convenient, for the resources available. Dugouts were dirty and wet, but undeniably expedient. Since the dugout dwelling had prairie Space earth for walls, it was usually abandoned in favor of Domestic have had a long history of surface sod-houses, which were somewhat freer of use both in rural farmhouses and urban townhouses. moisture and vermin. Still, the dugout was a Most often these were used for storage of foods and common structure on the prairie and far too fuel, but they also performed as an insulative air valuable to be left unused , even when the home• space between the heated house and the earth 's steaders moved topside; most often they were surface. Due to problems of dampness and lack of maintained for animal barns and food storage, in ventilation and illumination, house basements were addition to their emergency function as tornado disregarded as living spaces until the necessary shelters. (See Fig. 7) technology became available. Even with the advent of sufficient technology, basements suffered from a professional disdain. Frank Lloyd Wright, probably the most celebrated

architect of the 20th century , wrote in The Natural

I 1II1I1II1JJ11 House: Jil lliD. ; JJW "A house should - ordinarily - not have a basement. In spite of everything you do, a basement is a noisome, gaseous damp place. From it came damp atmospheres and unhealthful conditions . . . It usually becomes - as it became when I began to build - a great, furtive under• ground for the house in order to enable the occupants to live in it disreputably . " Not until the 1950's was the basement re-evaluated for its comfort advantage and given serious resi•

FIG. 7. "It was no uncommon incident for a dential attention . traveler driving across the prairie at night to drive over a dugout. Occasionally cattle wandered over the housetop shaking the dirt down onto the dining 1950: Climate Control table."(Dick {15}) In October 1949, House Beautiful began publica•

tion of its 2 year-long "Climate Control Project," Cass G. Barns, a Prairie physician , indicated that the first effort which claimed to apply the science two types of dugouts existed. The first was simply of climatology to house and community design. In a The Architectural Underground 7 series of regional analyses, the project came out in workshop and studios near Scottsdale, Arizona. favor of expanding underground living space for (Industrial Design) [22]. Soleri employs a system of selected climatic areas of the U.S. It was argued forming shells over earth mounds and then that basement space designed for living offers both excavating beneath the shells. By back -filling the superior comfort and greater economy (Lange• concrete structure with earth, these artificial caves wiesch) [19]. In that energy consumption is inex• become one with the desert , echoing the age-old tricably linked to climatic performance, this effort experience of the Berbers at Matmata. may be seen as a rediscovery of ancient wisdom and At the same time , architect Malcolm B. Wells was as the modem forerunner to our current interest in exploring the concept of "conservation archi• underground development as an approach to energy tecture" for his own homeland of the eastern conservation . It is difficult to assess how much of seaboard (Wells) [23 ,24]. Other architects recog• an effect the Climate Control Project had in nized the dissonance between modern construction promoting "lithospheric living," but finally the idea and the environment, and they also sought new was introduced to the modern professional and alternatives. Among these was architect John E. homeowner alike. Bernard, Jr., whose "Ecology House" in Marston Mills, Massachusetts, demonstrated that subsurface 1950's - 1960's: architecture could save energy and even lower With the 1950's came the cold war. As cheap fuel construction costs. (AlA Jrnl. [25] NAHB Jml., and air-conditioning weakened the apparent need Scope [26]) The energy-saving potential of under• for climate control, an increasing interest in civil ground construction has now captured professional defense competed for the propriety of use of under• attention, and has been the subject of several ground space. Subsurface building took on the investigations (e.g. Labs [27]) and a national simultaneous connotations of personal safety and conference regarding its application and ultimate public paranoia. Bomb shelters made underground usefulness. Inasmuch as energy conservation is space a hideous reality of fear and preparedness. related to climatic performance, and as climatic New public buildings were programmed with shelter response has always been a major theme of under • space; some buildings, private and public, were built ground space, it is safe to predict an optimistic entirely below ground for permanent shelter "new" future for expanded underground archi• performance. tecture. The Abo Elementary School and in Artesia, New Mexico, was one of these, as was Summary: Global Themes Rediscovered the Ethicon subsidiary of Johnson & Johnson A survey of world-wide examples shows the Company. Located in St. Angelo, Texas, Ethicon recurrence of several major themes regarding the use manufactures a large percentage of the world's of underground space. These include climatic supply of surgical sutures. Houses, too, were subject response, defensibility, symbolic or ceremonial to the move underground; builder Jay Swayze aspects, and issues related to local resources. Archi• constructed his own home under 3 feet of Texas tectural uses include habitation, animal shelters, soil in Plainview (Life) [20] , and offered a larger wineries (both old and new world), food storage model for public consideration at the New York areas, and churches, temples, and other sacred World's Fair in 1964 (Today's Health) [21]. chambers. Scale of application ranges from indi• Regardless of the merit of survival shelters, the vidual dwellings and storage areas to multi-level concern for civil defense made several important cities covering an area of several kilometers. contributions to underground development: it Historical incidences of underground development eliminated the novelty of underground buildings for generally occur in climates of severe hot and/or cold a broad variety of architectural applications, it gave extremes, with the greatest variety and distribution professionals a working familiarity with the physical occurring throughout the Mediterranean littoral zone. and psychological issues of subsurface design, and it The fluctuating seasonal extremes of many temper• has provided an opportunity to evaluate the actual ate zone climates has made underground develop• performance of underground environments. ment beneficial where problems of structure and moisture infiltration can be overcome. Evidence of 1960's - 1970's: Environment and Energy this can be found in the U.S., where a heritage of During the height of preoccupation with survival subsurface utilization exists for storage (in the shelter , a new interest in the potential of under• northeast and midwest), for habitation and storm ground space emerged . This concern was for shelter (the northern prairies), and for ceremonial developing an architecture of minimal impact - an and climatic reasons (throughout the southwest). architecture respective of natural processes and With the development of modern building ma• ecological stability. Architect Paolo Soleri demon• terials and methods, American interest in under• strated its application in desert regimes with his ground space has been revitalized, bringing forth

8 Kenneth Labs

new interpretations of old themes. Climate control, designed by architects in place of conventionally• defensive shelter, environmental preservation, energy surficial buildings. They are often a product of conservation, and multiple-level land use planning, unusual site circumstances, of peculiar design are among the "modern movements" to the under• programs, and of imaginative commitment to a high grounj. Both in accord with and irrespective of standard of design . Part II will examine the forms these movements there are now appearing a and functions of underground architecture in the remarkable number of underground s tructures modern world.

REFERENCES 1. Go ldfinger M. Villages in the Sun. Lund Humphries, London ( 1969). 2. LaNier R. Geotecture. University of Notre Dame (1971). 3. Cressey G. B. Land of the 500 Million. McGraw Hill (1955). 4. Rudofsky B. Architecture Without Architects. Doubleday (1964). 5. Fitch J. M. American Building: The Environmental Forces That Shape It. Ho ughton-Mifflin (1972). 6. Boyd A. Chinese Architecture and Town Planning, 1500 -1911. University of Chicago (1962). 7. Giovannini L., Editor. Arts of Cappadocia. Barrie and Jenkins, London (1971). 8. Rudofsky B. "Troglodytes," Horizon (Spring 1967). 9. Hazer F. "Cultural-Ecological Interpretation of the Historic Underground Cities of Goreme, Turkey," presentation to the conference Alternatives in Energy Conservation: The Use of Earth-Covered Buildings. Center for Energy Policy Studies, Univ. of Texas at Arlington (1975). 10. Kostof S. Caves of God. MIT (1962). 11. Allen E . Stone Shelters. MIT (1971). 12. Woodcock G. "Cave Temples of Western India," Arts (May/June 1962). 13. Owen C. H. L. "Lalibala," Architecture Plus (November/December 1974). 14. Sanoff H. "Seven Acres of Underground Shelter," J. Am. Inst. Architects (February 1967). 15. "Imprint-Baldasare Forestiere," Architecture Plus (July/August 1974). 16. Dick E. The Sod House Frontier 1854 -1890. Appleton-Century Co., (1938). 17. Barns C. G. The Sod House. Univ. of Nebraska Press (1930). 18. Welsch R. L. Sod Walls. Purcels, Inc. (1968). 19 . Langewiesche W. "There's A Goldmine Under Your House," House Beautiful (August 1950). 20. "Living It Up Way Down", Life (April 24, 1964). 21. "World's Fair Visitors View Life Underground", Today 's Health (September 1964). 22. Hamilton M. "So1eri: Architect-Designer", Industrial Design, (July 1964). 23. Wells M . B. "Nowhere to Go But Down," Progressive Architecture (February 1965). 24. Wells M. B. Guest editorial, Progressive Architecture (June 1974). 25. "Saving by Going Underground," J. Am. Inst. Architects (February 1974). 26. "Experimental Atrium House Built Completely Underground," Scope, Nat. Assoc. Home Builders (December 3, 1973). 27. Labs K. "The Architectural Use of Underground Space: Issues and Applica• tions". Master's Thesis, Washington Univ., St. Louis (1975).