94 



ALGERIA 



contour the hills. They are rarely, if ever, in ravines, except 

 when a boundary happens to follow the bed of a stream. Their 

 width is 5, 10, 15, 20, 25, 30, 40, 50, 100 (5, 10, 16, 21, 27, 32, 

 43, 54, 109 yards) and even 300 metres (328 yards), according 

 to the problems presented; along railroads the official width is 

 20 metres (21 yards) on each side. Boundary lines are ordina- 

 rily 10 metres (10 yards) wide, but in well-wooded country may 



FIG. 15. Cork oak after the cork has been removed, on a ridge fire line in 

 Algeria, Constantine Conservation. 



be as high as 25 (27 yards); these are constructed half on each 

 of the adjoining properties. 



In theory main fire lines are 100 metres (109 yards) and sec- 

 ondary lines 25 or 50 metres (27 or 54 yards), according to the 

 value of the stand. But this standard is flexible. At La Calle, 

 where dangerous conditions exist in valuable cork oak, there 

 is a line 300 metres (328 yards) wide. Yet in the Oran con- 

 servation, where there is but little cork oak, there are no lines 

 whatever wider than 50 metres (54 yards), and out of a total 

 of 386,164 metres (422,313 yards) of lines there are classified 

 as follows in metres and yards: 



