76 G. H. KNIBBS. 



sunlight as any general arrangement will admit of, and the total 

 absence of such for at least six months must be regarded as a 

 serious defect. Nor is this fact modified by the necessity that 

 may specially exist in some instances for deliberately avoiding 

 direct sunlight. Evidently, therefore, the direction of the streets 

 of a rectangular system should be placed in the N.E. and S. W., 

 and N.W. and S.E. positions. The diagram will at once shew 

 the effect of this, and the duration of direct sunlight on each face 

 of a rectangular building, making angles of 45° with the principal 

 cardinal points, will be as in the following table : — 



VI. — Duration of Direct Sunlight in Lat. 35° S., on each face 

 of a rectangular building set S.E., N.E., N.W., S.W. 



Time of Year. 





Face of Building. 









S.E. 



N.E. 



N.W. 



S.W. 



December 22 



4-50-11-10 



4-50-12-50 



11-10-7-10 



12-50- 



-7-10 



Jan. 19, Nov. 24 



5-0-11-0 



5-0-1-0 



110- 7-0 



1-0- 



-7-0 



Feb. 19, Oct. 24 



5-27-10-33 



5-27-1-27 



10-33 - 633 



1-27- 



-6-33 



Mar. 21, Sept. 23 



6-0-10-0 



6-0-2-0 



10-0 - 6-0 



2-0- 



■6-0 



Apr. 21, Aug. 23 



6-33-9-27 



633 - 233 



9-27-5-27 



233- 



-5-27 



May 22, July 23 



7-0 - 9-0 



7-0-3-0 



9-0 - 5-0 



3-0- 



•5-0 



June 22 



7-10-8-50 



7-10-3-10 



8-50 - 4-50 



3-10- 



■4-50 



The N.E. and N.W. faces have each eight hours of continuous 

 sunlight : and the S.E. and S.W. faces have from 6 J to If hours 

 or a mean of four hours, which also is the duration of direct sun- 

 light at the equinoxes. The signal advantage of this over the 

 east-and-west and north-and-south positions needs no comment, 

 and, since the case is similar in any part of the temperate zones, 

 it may be affirmed that the cardinal directions of a rectangular 

 system of streets should be inclined 45° to the meridian throughout 

 that zone. 



8. Width of streets. — The width of street desirable or necessary 

 in different parts of a city is a question depending on" various 

 considerations. From the standpoint of economy of construction 

 and maintenance, and from that of mere convenience in the 

 conduct of business, the narrowest street that will serve the pur- 

 pose, without intense congestion of vehicular and pedestrian 



