THE THEORY OF CITY DESIGN. 85 



In a city set out on the rectangular-radial system almost every 

 possible orientation in respect of individual blocks exists, and if 

 the site be also undulating, choice of aspect in such a system can 

 offer no difficulty, because of its multitudinous variety. So that 

 whether industrial or other requirements demand the presence or 

 absence of direct sunlight, those requirements are easily met. 

 Buildings in which it is necessary to secure the maximum pene- 

 tration of solar rays, so as to benefit by their heat in winter, and 

 the minimum penetration so as to avoid the heat in summer, 

 should so far as the geometry of solar shadows is concerned, have 

 their long axes east and west in southern latitudes and their 

 windows on the north face of the building. Since, however, the 

 temperature reaches a maximum after noon through the cumu- 

 lative effects of the sun's heat rays, the axis should, theoretically, 

 be rotated slightly, so as to turn a little to the north on the east 

 side, therefore a little to the south on the west side. The amount 

 of this rotation can be ascertained by taking account of the 

 difference between the apparent noon and the times of maximum 

 temperature; the differences between the noon and maximum 

 temperatures, and the latitude of the place considered, the 

 discussion extending over the changes for an entire year, so as to 

 properly integrate the effects, and hence deduce their mean. The 

 necessary rotation will, however, not greatly modify the E. - W. 

 position for the axis. The designer must, it is evident, take 

 account of these necessities, and for buildings of a large size, and 

 requiring spacious grounds, where aspect is important — as for 

 example hospitals, sanatoria, etc. — provide suitable blocks. 



15. The cesthetics of design. — A study of those examples of 

 architecture which impress the human consciousness with a sense 

 of beauty, has revealed the fact that their general proportions, 

 and the mutual relationship of their details, conform to simple 

 numerical ratios and to an harmonious scheme. These ratios, 

 spatially realized in the cube, square, the plane or circular equi- 

 lateral triangle, the 3, 4, 5 triangle, the sphere, cube, pyramid, 

 etc., are geometrical forms that constitute, as it were, a skeleton 



