PRACTICAL AND AESTHETIC PRINCIPLES FOR THE LAYING OUT OF CITIES
F.[i.e. Josef] StubbenFirst presented at a meeting of the Deutschen Vereins für öffentliche Gesundheitspflege, held at Freiburg, Germany, in September, 1885. The translated text by W. H. Searles, M. Am. Soc. C.E. was issued as an Advance Copy of a portion of the Transactions of the American Society of Civil Engineers of 1893. Its publication was part of the meeting in Chicago of the International Engineering Congress of the Columbian Exposition, 1893. It was criticized on one point by James Owen, an American engineer.The laying out of cities is accomplished in two ways: either in the course of additions to an existing settlement, by gradually extending the present roads and occasionally establishing new roads, as the number of buildings without reference to one another is increased; or, by establishing a general plan for new streets and street repairs, according to which the intended construction is to be realized. The first way has been called the natural, and the layout the artful, method of laying out cities. This is a false definition, for it does not answer the natural purpose to let the buildings string themselves together regardless of plan; and it is not an artificial acquiescence, but practically a confirmed necessity, that the laying out or spreading out of a city should proceed upon the basis of a well-considered, comprehensive plan. It is more correct, therefore, to call the first method of city building the arbitrary, and the last the systematic. We have here to do only with the systematic or regulated laying out of cities.
Stübben (1845-1936) was then Assistant Burgomaster and Royal Counselor of Buildings in Cologne. He was a Berlin-trained architect who was appointed head of the office of city planning, first in Aachen from 1876 to 1881 and then at Cologne. During his career he was involved in city planning studies of more than thirty cities in Germany and abroad. As one of Europe's best known planners, Stübben received invitations to present papers at dozens of professional meetings.
He incorporated these materials in his major publication: Handbuch des Städtebaue whose first edition was published in 1890 and revised and expanded versions followed in 1907 and 1924. In its final state it included 900 illustrations, scattered through thirty chapters and twenty- three appendices. The statement below is an attempt to summarize the important points that his handbook covered.
The essential basis of regulated city-building is the establishment of future streets and places, and, consequently, of the plans for them. Here we regard not so much the technical improvement of the streets, or street-building proper, but rather a very skillful, consistent connection and complete network of streets, requisite for the traffic and growth of the city, the residence and joint life of the citizens. We are constrained, therefore, to develop the mere street plan into a building plan, or, further, into a city plan, i. e., a design in which, out of the network of streets and building areas, are arranged all those constructive regulations as well, which are demanded for the life of the city.
The practical principles of such a plan of city construction relate to traffic, to building and to health. Moreover, aesthetic principles are to be followed which concern the construction of streets and public squares and their relation to edifices.
I. Practical Principles
a. Traffic.--The streets and squares of a city have first of all to fulfill the demand that they accommodate the city traffic in the most perfect manner possible, for to serve the traffic is their most important duty.
The designer of a city plan has therefore to ascertain and establish, first of all, the real lines of traffic of the present time and of the future, so far as they can be foreseen. The first of these traffic lines are everywhere those which lead from the middle point of the city to the outskirts and the reverse. Their direction will be planned along neighboring districts, railway stations, harbors, places of amusement and other iterative points of the vicinity. It forms, therefore, a net of radial lines or rays, as a glance at the map of an old city instantly teaches. The radial streets are on this account the first and most important in the design of a city plan to establish the members of the network of city streets. They divide the city and suburbs into a series of sectors. As the size of these sectors increases toward the exterior, there arises the necessity of subdivision by means of radial lines of a second order, to the end that all the improved tracts may be conveniently reached from the midst of the city.
The second sort of traffic lines are such as serve the purpose of connecting the several sectors. They have in general a course like concentric circles around the central point of the city. These are the "ring streets," which are readily distinguished as of the first, second or third order, etc., according to their signification on the city plan. In extended ground plans of a city the radial and ring streets often take on the form of longitudinal and cross streets.
Radial streets and ring streets always approach each other perpendicularly. They divide the improved districts into lots of trapezoidal or approximately rectangular form. For obtaining proper building blocks a further division of these lots is necessary. These blocks are formed by using by streets which run approximately radial in one direction and circular in the other, so that the city plan will finally consist of a multitude of building blocks which altogether are more or less rectangular. Thus the traffic lines between two points which do not lie on the same street always consist of two legs at right angles to each other. From one extremity of the hypothenuse[sic] of a right- angled triangle to the other, one cannot go directly, but must always travel along the other two sides.
This does not correspond to the demands of traffic. The insertion of the hypothenuse[sic] is necessary, or, what is the same thing, the larger trapezoid or rectangular divisions must be traversed by diagonal streets before the subdivision by an approximately rectangular scheme of by streets is undertaken. The diagonal streets are to lie so that they will practically connect the chief focal points of the traffic directly with each other. These focal points are either given localities, such as railway stations, bridge terminals, landings, markets and the like, or they will be formed artfully by the junction of several streets. In the last instance occur the so-called "traffic places" as to which it is the problem to interpose an avenue from the one center of travel to the other.
The system of streets must be qualified to serve, not merely the ordinary foot, saddle and wagon travel, but in the design of the network care should be taken that crowds may form in large numbers which street railways with animal or mechanical power may be able to take up.
The four kinds of streets, the radial, ring, diagonal and by streets, unless special reasons oppose, are so designed that existing roads and real-estate boundaries are followed if possible. This is only necessary for the existing highways comprehended in the built-up neighborhood; for other roads and property lines, the requirement is not essential.
The grades of the streets are to be made as convenient as possible for the traffic: the maximum to be according to local circumstances from 1 to 10%; the minimum, for the sake of drainage, 0.5 to 0.2 per cent. It is desirable that the streets should lie slightly above the general surface (say, 1 m.). Heights of 3 m. are ill-advised. greater embankments and excavations are undesirable, because they increase the cost of improvements considerably, and require as a rule the grading of all adjoining property.
The width of streets should correspond to the expected traffic. It should be at least 10 m.; more than 40 m. is required only in the rarest instances. As to wider streets the claims of health and beauty give the proportions.
Transversely, the street is to be divided into at least one roadway and two raised sidewalks. A certain amount and kind of travel requires a special walk or promenade in the center of the street, a special bridle path or the division of the roadway for teams and equipages, giving rise to various cross-sections, and so much the more, when, for reasons of health and beauty, the streets are set out with rows of trees and flower beds.
Thus far we have considered only the traffic moving along city streets, but not less has the designer of city plans to regard those kinds of traffic which follow independent ways by, under, or over the city streets, viz.: Railroads (local and through), canals, wharves, docks, etc. care should be taken to provide suitable space on the plan for the management of this sort of traffic adjoining the proper depots, harbors, landings and freight yards. To follow closely here the requisites of such a traffic-plan would exceed the bounds of the present problem, and would lead into technical domains which do not belong to city- building proper. Yet often it is a necessity to establish the arrangements for the great traffic before the city map can be generally projected in detail.
b. The Buildings.--The meshes of the network of streets are as a rule termed the blocks. Their shape is rectangular, trapezoidal or triangular. The last form occurs especially along the diagonal streets. Various other shapes of blocks are occasionally found. The notion that acute-angled blocks are to be generally avoided on account of the difficulty of building on them, is incorrect; for, in the first place, conformity to the plan of traffic lines brings out sharp-angled blocks unconditionally, and, furthermore, the inconvenience in building is easily overcome, and indeed is availed of to bring about commercial and artistic advantages.
The sharp corners of the blocks are to be taken off. The amount to be cut off increases as the angle grows less, and should be large enough to provide for a facade on the corner. Instead of cutting away the corner it may be preferred to round it off; also, right-angled corners where a very large traffic occurs need to be cut off or rounded off. Generally, however, to accomplish this is neither necessary nor handsome. The cutting off of the obtuse angle of a block is only to be recommended in exceptional cases.
Within the blocks the boundary lines of the building lots should be drawn at right angles to the range lines of the streets bounding the same, so that in triangular, trapezoidal or irregular blocks buildings with oblique angles may occur only at street corners. Thus, oblique angled property offers no difficulty in opposition to judicious and artistic building.
In case the lot lines are not perpendicular to the street, then, before building is allowed, the lines are to be so shifted by mutual exchange of equivalent areas that right-angled plots will everywhere obtain. If the change of lines cannot be obtained by the voluntary agreement of all owners, it becomes necessary to enforce the change by legal means notwithstanding the opposition of individuals.
In right angled blocks the depth is equal to the entire depth of two building lots abutting one another in the rear. Therefore the depth of lots, usual to the place or necessary for the future, fixes the depth of the blocks. Whatever the normal depth of a lot, the depth of the block is twice as great. In triangular or other blocks with diverging sides, the proportional depth is fixed by analogy with the foregoing. The length of the blocks may amount to about 1 1/2 to 2 1/2 times their depth.
Factories and other industrial improvements require large blocks, say, 100 m. deep by 200 m. long, and should be so situated that the street and track connections with freight depots and harbors are easily obtained.
For private residences with gardens, medium-sized blocks are well adapted, say, 80 m. by 160 m. Property for rental and business houses which would be used as much as possible without gardens, may be judiciously divided into rather smaller blocks, say 60 m. by 120 m. Workmen's dwellings, finally, require smaller lots and, therefore, smaller blocks, say, 35 m. deep. The length can be increased to, say, 140 m. without disadvantage.
In dimensioning building blocks, however, there are to be considered the requirements, not merely of the individual, but in a greater degree of the public, that is, of the state, the parish and the corporation. Care is to be taken that blocks and parts of blocks be provided, suitable in position, shape and size for the erection of churches, high schools and common schools, for government buildings and courthouses, theaters, museums, concert and amusement halls, exchanges and banks, post and telegraph offices, markets and slaughter houses. If it is not possible for the city of the future to determine the size and place, collectively of all the public improvements above mentioned, still the plan of the city should anticipate a sufficient number of building lots and blocks in convenient situations, which are proper to be used for public buildings as soon as the necessity arises. It is a mistake to refer the undertaking of such monumental and specific buildings haphazard to the later search anywhere for a half-way suitable place on a once-adopted building plan.
Many edifices, such as churches, theaters, museums, etc., require an open space, if not all around, at least on three sides. Many public buildings need a plaza even for traffic, while it is desirable to give others an axial position relative to the direction of a street, so that they may be readily found. All such claims are easily satisfied when laying out a plan of streets, but later only with difficulty and imperfectly.
c. Health.-- Under the supposition that the climatic conditions of a country generally decide the settlement of a great mass of people in one place, the first condition, in the interest of health, for the building or enlargement of a city is freedom from overflow and, therefore, a site above high water- mark, or a protection against flood. If the site is not free from overflow, protection must be brought about by artificial means, particularly by lowering the water surface, by raising the land surface, or by dikes with or without pumps.
A second condition is the dryness and cleanliness of the subsoil. It is important that the ground-water surface be not found in, nor occasionally rise into, those layers of sand which will be essentially changed or rendered impure in their condition under human settlement, and that, finally, the surface of the ground possess a form which renders an easy discharge of water possible. If the ground-water rises too high, it is prejudicial to health by inducing fermentation in the organic portions of the sandy stratum, prevents the use of cellar rooms, renders difficult the drainage of the surface and permits, through the absorption of waste material, the pollution, which is calculated to occasion danger to health, in water used for drinking and other purposes. In such cases before the soil upon a city plot is fit for use, the ground-water surface must be reduced, and its further rise prevented by a systematic subterranean annualization.
If the surface of the city ground generally shows a continual descent, the subterranean canalization can be, evidently, dispensed with for carrying off storm water. Here, however, as the city expands, the street gutters which have to carry off the rain water, require ever a larger cross-section; so, especially, the crossings of the streets with such gutters is very disturbing to the traffic, and so, for the draining of the surface, a network of subterranean channels soon proves to be necessary. Still, a gradual slope of the surface is important, because, in troughs and depressions of the ground without natural outlet, heavy rain storms may produce troublesome overflows notwithstanding the sewer system.
But, finally, the subterranean system of sewers is needful to carry off the domestic and industrial drainage and human waste material. As a rule, the combined system of sewers has shown itself the best for all three purposes described; under certain circumstances, however, the arrangement of two or more separate sewer systems for ground-water, for rain, for house and industrial drainage, for faecal deposits, may be judicious.
The general provision of good water for drinking, cooking and other uses is indispensable, as the subsoil of larger cities, even with the best endeavors to keep it pure, is undoubtedly incapable of furnishing drinking water. The combined provision of wholesome, faultless water is to be preferred to the separate provision of drinking water and water for other purposes.
The fourth requisite for health is light; not merely the diffused light of the atmosphere, but also the direct light of the sunbeam. For the distribution of light, the direction and width of the streets is limited by the height and kind of buildings. The east and west direction of streets is itself advantageous, because it brings the unimpeded sunbeams to front or rear of both rows of houses. But it has the disadvantage that upon the streets at right angles--that is, north and south--the front of one row of buildings and the rear of the other are entirely deprived of the direct rays of the sun. The practical view shows, however, in accordance with the scientific theory, that in a system of right-angled or approximately right-angled streets, not the directions of north, south, east and west, but those intermediate directions of southwest, northeast and northwest, southeast are most favorable to direct sunlight. Diagonal streets in such a street system have a very favorable position for illumination, but diagonal streets from south to north have a correspondingly unfavorable position.
In reality, however, the considerations of traffic and buildings allow the designer of a city plan so little liberty that the orientation of the streets with regard to the sun is but seldom of decided significance in the regulation of a network of streets. Furthermore, it is feasible in the arrangement of the buildings to have regard to the sunshine. The restriction as to height of buildings and number of stories, the sufficient regulation of larger building spaces, the arrangement of ground plans of buildings, and particularly of the sort of additions and wings so that no living-rooms, or as few as possible, may open their windows only on the north side; these are not in point to be further followed here, since they will be duly considered in the copies of the regulations of the building police and in private building activity. It is possible to shape dwellings satisfactorily in relation to sunshine, although the streets may not possess the most advantageous orientation.
Rooms without direct sunlight are, however, not to be altogether avoided in general; they are even a necessity for certain industrial and artistic employments. For such rooms an abundant provision for diffused light of the atmosphere is so much the more important. This leads to the demand so to arrange the buildings that, at all events, in dwellings and other abodes, the rooms serving human needs may at least get a sight of a patch of sky under an angle of 45. Thus, it may be guaranteed that the diffused rays of sunlight spread in the atmosphere will generally enter residences and living-rooms without being weakened and altered by reflection on the front of buildings or courtyard enclosures. But still this demand of not giving up the direct sunlight, which always presupposes that both in streets and in courts the height of buildings shall not practically exceed the distance between them, has thus far not been able to be realized in any city, through either the building directions of police or voluntary attention. In reference to this the effort has everywhere been, out of regard to cost, to enhance the usefulness of the building ground, in preference to studying hygiene. It is our duty, in the design of city building plans and building designs ever to bring into higher value the demands of public health with respect to supply of daylight.
For supplying the streets and buildings with artificial light by night, the illuminating gas, by reason of its consumption of oxygen and production of heat and of gases detrimental to health, does not wholly fulfill the hygienic requirement. The electric light, on this account, is to be preferred.
As a fifth hygienic requisite of city construction we have to denote care for the adequate amount of fresh air. And, indeed, there is needed a plentiful supply of air on the streets, in the blocks and within the buildings themselves. The aforesaid condition, that for the sake of light the height of buildings ought not practically to exceed the space between buildings, brings about on the streets and in the courts a sufficient airing. The streets and open courts, according to this, ought not to be less, or not materially less, than the houses are high; indeed, according to the customary height of houses, a breadth of free space of at least 10, 15 or 20 m. is necessary. For streets in the newer portions of a city this demand is easily realized; as for the courts, they are easily restricted, for the most part by the value of the ground. But besides these most restricted dimensions of the air channels of a city, there are greater stores of air necessary, by the help of which the change of air in the narrow channels can be consummated. Open squares serve this end, which interrupt the system of streets even at such places as the traffic alone does not call for; furthermore blocks with interiors free from buildings, to contain gardens; and finally, districts of the city in which buildings will be allowed only with open spaces around them (country house districts) serve the same end. Such reservoirs of air can be formed by voluntary consent of property-owners; in default of which, they are to be provided compulsorily by the official establishment of city- building plans, so that free plazas be kept open in the street system; that by retrograde building lines the interior of certain large blocks be kept free of buildings; and finally, that in designated parts of the city continuous rows of houses be interdicted.
In a particularly effective manner will the improvement of the air in the city be promoted by providing, on the established city plan, for a liberal setting out of trees. These serve, at the same time, a fifth hygienic interest, which consists in this-- that the movement of the populace on pleasant shady paths will be made possible and easy. For setting out trees the streets and plazas are suitable, besides which care must be taken to provide for public gardens and parks and for promenades beyond them.
Streets with shade trees require a greater width than is necessary for traffic, or simply to provide light and air. The least width of a street planted with a row of trees on each sidewalk is about 20 m.; a width of 25 or 30 m. would be better. For planting a row of trees on a separate walk in the middle of the street a width of at least 26 m. is required; widths of 30 to 35 m. are better. Four or more rows of trees require still wider streets, so that the rows may be at least 6 m. apart. Instead of increasing the rows of trees it is often desirable to induce front yards between the streets and buildings, or to lay out strips of garden plots with grass and ornamental shrubs within the street lines. It is self-evident that this sort of improvement is fit only for those streets where traffic can be dispensed with.
Just so the planting of open squares and places which are required for traffic must not be demanded. Besides rows of trees and strips of grass there will be established whole gardens or small parks which either are open and to be crossed by all sorts of foot-travel, or are inclosed and serve only for quiet retreat. The latter, with high walls, are especially of great value to health. They come to be so by lessening street dust, by giving shade and by cleaning the atmosphere, and furthermore by this, that every such improvement affords opportunity for refreshment and recreation.
In addition to these, however, public parks of greater expanse are a hygienic necessity, wherein the people may take exercise in the open air. There are artificial landscapes of from 5 to 100 or more hectares in extent, which, under the titles of city gardens, people's gardens, burger parks, and the like, together afford the public bodily exercise (school play, football, croquet, lawn- tennis, skating, etc.), for the people's amusement and recreation.
The precise area which can be afforded in a city for tree planting is not easily specified. The local circumstances and means are in this respect extremely various. As a minimum it may be estimated that at least one-tenth of the city surface will be planted, and that at least 3 sq. m. of planted ground will fall to every inhabitant. The improvements outside the city limits are not included in this estimate.
The outside improvements, which ought to give the city population opportunity and inducement to further promenade or outing, are either connected pleasure grounds (e. g., a natural or artificial grove) or streets and roads which will be beautified by rows of trees or landscape gardening wherever it is possible to lead to places of refreshment, or to afford a pretty outlook. The designer of a city building plan has to provide for such hygienic arrangements in the suburbs with the greatest care.
A sixth essential of a city building-plan is, lastly, the judicious local disposition of such public or private arrangements as injure their neighborhood with regard to the health or pleasure of the inhabitants. For slaughter-houses and cattle-yards, for hospitals for the treatment of contagious diseases, and for churchyards, proper situations are to be provided. The carrying on of trades which through evaporations or noise bring danger or become burdensome is to be confined to appointed parts of the city.
II. Aesthetic Principles.
The building plan of a city in the wider sense, or the street plan in the narrower sense, ought not merely to satisfy the practical requirements of the traffic, of the building and of health; it ought also to be laid out on aesthetic principles, i. e., in such wise that it may give an impression of beauty in all its parts, or, what, is the same thing, may awake in the beholder a disinterested satisfaction. As the fostering of beauty in all arts is the most eminent problem, so the beauty of the outward appearance in the art of building cities is of superlative importance The art of city-building, which the city population every where comes in contact with, is more than any other branch of art practice an art for the people. If, with the cultivation of beauty, the associated influence of heart and soul be aimed at, we may anticipate from the aesthetic perfection of the building plan of a city, a rich and blessed influence upon the stratum of city population inclined to rudeness. At the same time, however, as well for the cultivated as for susceptible minds in general, it is a spring of pleasures and enjoyments. The considerations of the beautiful relate to the perfecting of the streets and squares in themselves, and in their relation to the buildings.
a. The Perfecting of the Streets and Squares.--The streets should not be too long. Too great length of street wearies the eye, wearies the spirit and awakens a feeling of discomfort. The danger of this unpleasant sensation begins as soon as the length of the straight streets amounts to 20 or 30 times their width. Should, however, a change of direction be undesirable for practical reasons, there remains the remedy against the tiresome effect of subjecting the street to variations in its width and cross-section.
For the regulation of streets, straight lines ought not to be exclusively employed. Gentle curves which conform to superficial outlines or to natural boundaries may produce fine effects in the form of the streets. It is not necessary that the two sides of a thoroughfare should be always exactly parallel; a pleasant effect may follow, at the opening of squares, from the irregular widths of streets due to a junction with older parts of the city and by interference of property. The bow-shaped avenue is preferable to the polygonal form, or strictly, a bow-like polygon of which single parts answer to the widths of the houses.
A street ought not to be conducted in straight lines over a summit; that is, convex changes of grade are to be avoided. The reason of the unbeautiful appearance of this sort of convex streets lies in the apparent sinking of the buildings, wagons and people beyond the ridge of the street. Passing over a high point has to be accomplished by bending the street level in plan and profile, the course of which the eye cannot follow beyond the ridge, or by means of breaking off the street at the summit. The interruption may be a vertical or a horizontal one; a vertical in the form of a monument, a plantation, a fountain, or the like which the eye cannot see beyond; a horizontal in the form of a crossing or dispersing place beyond which the direction of the street changes.
If the convex street is unhandsome, the concave profile creates on the contrary a special advantage. It affords to the street surface by day and by night a pleasing spectacle and may produce with artificial lights magnificent results.
The street surface ought not to be too wide, because the void does not satisfy the eye nor the mind. If the street surface cannot or should not be beautified with rows of trees and garden plots, a width is to be preferred restricted to traffic and health.
All portions of the street surface unnecessary to traffic are to be set out with ornamental plants or artificial ornaments. Rows of trees and garden spaces have been already mentioned. Artificial ornaments consist not merely in monuments, graceful statues, water-jets, flowing fountains, gate structures, arcades, and other works of architecture and sculptural art, but also in the tasteful and well-modeled improvements of requisite utility upon the streets, such as trading stalls, waiting rooms for street railways, necessary establishments, columns for posters, fire-announcers, drinking stands, lamp-posts, candelabra, lanterns, street-signs, warning-boards, boxes for sweepings, enclosures, and tree-boxes. To the artistic sense and artistic gift of form, pleasure is given by all these, for the most part subordinate, objects, and thus they come to contribute to the pleasing and agreeable appearance of the street scene.
Finally, it is important in the improvement of the streets to provide for frequent change. This change should relate to street widths, the widths and regulation of driveways and walks, the number and position of rows of trees, the artistic ornament, the garden surfaces in the streets and front yards, the kind of house-buildings (closed or open, high or low buildings). Every street, or at least every prominent street, should be handled and improved for itself individually, so that it may afford a characteristic appearance. The wearisome and unhandsome uniformity under which so many modern streets suffer may be in this manner effectively avoided.
All the foregoing remarks upon perfecting the streets apply in largest measure to the public squares. They should not be too large, nor bounded by exactly right lines, nor have any summits; they should utilize the advantage of concave surfaces; they should be adorned with trees set out, with garden plots and artistic ornaments, so far as the traffic and the considerations in the following paragraph permit it to be done; and they should present an individual variety in their setting out.
The business squares decidedly require openings on all sides; their free surfaces serve the walking and driving travel. All other squares need the closest surroundings possible, because, primarily, by means of the enclosure the place rises in an architectural sense; the wagon travel may be permitted around the border of the parks, but not across the open parks.
b. The Relation of Streets and Squares to the Buildings.--The streets of the city are not merely for the purpose of serving the traffic, giving an opportunity for the improvement of real estate, and by their air spaces making plantations and establishments useful and beautiful, but they are also destined to bring our structures into agreeable position and effective grouping. The latter applies in an especial manner to monumental works of architecture and sculpture.
According to aesthetic laws, there are four different distances to be distinguished for viewing buildings and statues, viz., a distance equal to the cross-sectional height of the work, which is specially suitable for observing the individual structure; a distance equal to double the height, around the work or form for its own benefit; a distance equal to three times the height, in which the work, united with its surroundings, makes a part of the joint architectural idea, and a fourfold and greatest distance, which only permits a dispersion of masses and development of outlines, and produces a picturesque aspect of the city.
From which it follows, if a monumental edifice is to be erected within the ordinary street lines, the width of the street should not be less in any case than the height of the contemplated structure; but it is better to bring the street to one and a half or twice the measure. Should the latter be impracticable for the whole length of the street, the widening should occur directly in front of the structure, since the structure will be set back behind the street lines, in order to obtain front space and thus a distance of sight. Instead of setting back the building, the corresponding place on the opposite side of the street can be set back, so that the open space is obtained on the other side of the street. In curved streets the concave side, to which the sight is always directed, is chosen for erecting monumental buildings, because more suitable than the more hidden convex side of the street.
But the appearance of a structure is more effective if in the original establishment, or the later completion of the plan of the city, the street system is so laid out that a monumental work forms the objective point (closing point) of a street, or of several streets; and furthermore, an elevated locality is assigned to such buildings. The axial and elevated erection of monumental buildings enriches and beautifies the appearance of the city, and serves at the same time the purpose intended, as it makes it easy to direct one's way in the network of streets.
We should beware of too frequently occurring faults in the axial arrangement of streets and monuments, namely, of exaggerating the distance of view, and of obstructing the traffic. According to the aforementioned aesthetic principles, the monument already begins to lose its architectural effectiveness at a distance of four times its height; there remains only the effect of picturesque masses and outlines. But these, too, lose their signification if by a very great increase of vista the scale of objects is too much reduced. Statues are, on this account, particularly unsuited to street intersections, and architectural works, as a rule, should not stand free to view at a greater distance than such as corresponds to 10 times the height. Also, a monument ought not to be of the kind to interrupt a line of traffic which would be compelled to go around the structure, in order to set forward again on the further side in the same direction as before. The monument should rather occupy the effective street intersection at which a natural turning aside or separation of traffic occurs.
Still more than the shaping of streets does the improvement of public squares stand mutually related in artistic effect to buildings and monuments erected on or near the squares. The determination of squares as traffic areas, as air reservoirs, and as shaded places of recreation will be subordinate to the question how they may serve as a place of setting up the more important works of architecture and monumental art. The erection follows so that the buildings and monuments take up a position either upon the area of the square, or they surround the square, or both kinds of erection are combined.
If the square is built up with a structure standing free all around, a space must be left open in front of the building at least of such width that it may serve as a plaza so as to offer the sufficient distance for observation. Here especially a distance equal to double the height is of importance. The other parts of the square have then merely a nearly neutral significance.
Instead of one front space, two or more are often arranged, in order--besides the front view, which is still important--to bring into value other aspects of the monument. With monuments of great extent this arrangement, which results in the division of the entire square into a group of squares, is specially judicious. In this connection care should be taken to secure the most feasible complete enclosure of each one of the partial squares.
In a similar manner, too, should sculptured monuments, if they occupy a public square as a masterpiece, be so placed that the larger portion of the area should extend in front of the statue for its better observation, while the other parts of the square have a more restricted significance. The exceptions are such purely architectural monuments as columns, obelisks, fountains, etc., which are equally important on all sides. These may occupy the middle point of a square. Another kind of arrangement is adapted to an elongated place. It consists of a row of figures or monuments occupying the longitudinal axis, so that a masterpiece may adorn the middle point.
If the place is surrounded with several buildings, and has an open area, there arises the most distinguished creation of city construction. The most careful weighing of proportions is here especially important, in order to obtain the appropriate distances of observation. High structures come to stand at the ends, and low ones along the sides, of a place. A space of view of double the height is essential to comprehend the form of an edifice; a threefold distance is necessary, in order to enjoy a general view of a group of buildings. It does not require symmetry in a geometrical sense; but the buildings should so surround the place that an artistic balance may everywhere prevail, that the enclosure may appear complete, and that the outgoing streets may not break up the design unfavorably. In many cases the breaks may be abolished or avoided by portals built over the street exits.
These statuesque figures standing along the sides are suitable to complete and embellish the surroundings of the place. To every work can the just distance of view be thus afforded, while it contributes in general form to the artistic effect of the whole.
The combination plan of building upon and around the parts of a square is truly difficult, but still is accompanied by the loveliest artistic effects, if it fulfills the aesthetic considerations which are the limitations of building and monumental work in the various positions. It requires great exercise of a well-developed artistic feeling to strike the right thing. It is only to be decided in a so-called picturesque that is, irregular, laying out of a place and free groupings. These often occur, too, in modern intelligently managed city plans where it depends upon bringing into harmony historical structures with new creations.
I. Practical Principles
a. The city traffic demands the laying out of radial, ring, diagonal and by streets, as well as business squares and focal points. A mere rectangular system is unfit for a street plan.
The laying out of the street roads is to be regarded. The profile of the streets should be the flattest possible, but drained, the embankments not to be too high. Excavations are to be practically avoided. The width and cross-section of streets should answer generously to the amount and kind of traffic.
Also for traffic not done on the streets (railroad and water- way traffic) the layout of the city must have a care.
b. The blocks formed by the network of business streets are suitable for city construction. Sharp-angle corners are to be rounded off.
Within the blocks the property lines are to be swung into rectangular position by either voluntary exchange or legal compulsion.
The layout of the city has to provide blocks of different sizes in suitable places, such as are requisite for business operations, private houses, rented houses, stores and workmen's dwellings.
Also, blocks and parts of blocks are to be provided in suitable size and place for erecting public buildings,
c. For reasons of health, the city ground must be free from over flow, or protected; the soil must be kept dry and clean.
An underground system of sewers is indispensable to the removing of atmospheric precipitates, the domestic and industrial waste water, and human excreta.
General provision of good drinking water is necessary.
A sufficient provision of atmospheric light and of direct sunlight is to be served by a judicious orientation of the streets towards the cardinal points and a generous width of the streets; but, better still, by a rational arrangement of the habitations within the blocks. For night lighting the electric light is preferable to gas.
The providing of the city with fresh air requires, besides sufficient width of streets and size of yards, open squares in the street system and gardens in the building blocks; such further districts as will allow only separate buildings to be erected; and, finally, shade trees on the streets, squares and separate parks. The plantations, consisting of rows of trees and garden levels, seem not merely to purify the air, but cause the city population to take bodily exercise, and levels recreation and refreshment.
The city layout has to provide special districts for industries injurious to health or annoying, or to lay down local restrictions.
II. Aesthetic Principles.
a. The elegant development of the streets requires the restriction of street-lengths, the variation of straight and curved street lines, the avoidance of convex and the preferring of concave changes of grade, the avoidance of street spaces all too wide and vacant, the setting out of the streets with horticultural and artistic decorations, and, furthermore, the individual handling of single streets, but not in a pattern-like way.
For the elegant development of places the same points of view are to be regarded. Convex shape of ground and excessive size of vacant levels are to be avoided; individual establishments are to be opposed, so far as the design permits to bring about complete enclosure, and to keep the lawns free from carriage roads across them.
b. For obtaining an elegant proportion between the streets and places on the one hand and the buildings on the other, the following rules are useful: Choice of street-widths not narrower than the height of buildings; arrangement of spaces in front of important structures; preference of the concave side of streets; putting prominent structures in an elevated position and at the objective point of one or more streets, while avoiding, however, the embarrassment of traffic and trespass upon visual distances; furthermore, placing a structure upon an open square, so that a front space, or several parts of a square, suitably enclosed and of sufficient size, may be kept free for observation of the structure; placing one or more monumental buildings on or around an open place, suitable visual distance may be everywhere afforded, the artistic equilibrium produced, the enclosure made complete and the separation of forms avoided.
Monuments of a figurative art are not to stand at the middle point of a square; this is permissible only for all-around homogeneous works of architectural art. Arranging them in rows on the longitudinal axis is seldom judicious, and standing them around the border is frequently so, and the bringing about of a correct distance for observation is necessary.
For the irregular arrangements of picturesque art, the artistic feeling is alone proportionate.
Selected, scanned, edited, provided with headnotes, and formatted as a web document by John W. Reps, Professor Emeritus, Department of City and Regional Planning, West Sibley Hall, Cornell University, Ithaca, New York 14853, USA. Tel: (607) 255-5391, Fax: (607) 255-6681, E-mail: firstname.lastname@example.org To Top of Page To Homepage