DAYLIGHT SAVING. I5I 



So the rirst poim to consider is. what would be the effect, 

 if in summer time clocks were advanced one hour on present 

 standard time or. in other words, we adopted as our zone 3 hours 

 E. of (ireenwich. Then Ca])etown clocks would be no less than 

 I hour 46 minutes in advance of mean time, whilst Johannes- 

 l)urj,^ would benetit to the extent of i hour 8 minutes, and 

 Lorenzo Marques by 50 minutes. 



To consider the eifect more closely, let us assume that sum- 

 mer time will be used from the ist October until the 31st March 

 — that is. six months out of the 12. We will only consider three 

 towns, as the circumstances for others are not essentially dif- 

 ferent : — 



Ca])eiown : h. m. 



( )ctolier I. — Sun would rise at 7 2"}^ summer clock time. 



Sun would set at 7 48 ,, „ ,, 



March 31. — Sun would rise at 7 59 ,, „ „ 



.Sun would set at 7 40 „ ,, ,, 



Bloenifontein : 



October i. — .Sun would rise at 6 53 ,, „ ,, 



.Sun would set at 7 17 ,, „ ,. 



March 31. — Sun would rise at 7 25 ,, „ 



Sun would set at 7 12 ,, ,, ,, 

 Maritzburg: 



October i, — Sun would rise at 6 37 „ „ „ 



Sun would set at 6 59 „ „ „ 



March 31. — Sun would rise at 7 9 „ „ ,, 



Sun would set at 6 54 ,, „ „ 



These are the actual clock times that the sun is on the 

 horizon, because of twilight, daylight is roughly 1 hour longer, 

 namely. 30 minutes in the morning and 30 minutes in the evening. 



Thus the eiTect at Ca])etown would be that, if a person 

 usually gets U]) at 8 o'clock he would, during " summer time," 

 do so when there had been at least half an hour of daylight, 

 and if he finished work at 5 o'clock, he would have at least 3^ 

 hours of daylight for recreation, etc. There is no disability in 

 getting up at dawn in summer time in Ca])etown. because it 

 is a genial climate. Capetown will economise a lot by ado])t- 

 ing these earlier hours. 



Similarly, a person at Bloemfontein rising at 8 o'clock will 

 do so when th^re has been at least one hour of daylight, and he 

 will have over three hours of daylight after 5 in the afternoon. 

 At ^Maritzburg the condition of affairs, even making allowance 

 for its surrounding hills, is in much the same circumstances. 



In the height of summer, that is, in December and January, 

 there is a ])ositive advantage in starting wcjrk earlier, because 

 one can eret about before the heat of the dav has fairlv set in. 



