Popular Science Monthly 



941 





A Rope Suspension Bridge for a 

 Garden 



SUSPENSION bridges present a very 

 artistic structure for spanning small 

 streams or a brook on the grounds or in a 

 park. The illustration gives the details 

 of such a bridge and tables of proportions 

 for construction of the different lengths. 



The concrete posts which hold the 

 upper cord of the bridge are built and 

 reinforced as shown in Fig. 1. The 

 suspension cable is secured to a drive 

 anchor, expanding anchor or dead man 

 and then run across the ravine and se- 

 cured on the opposite side in the same 

 manner. Both suspension cables should 

 be the same length and have the same 

 amount of slack or sag. The lower cord 

 is drawn as taut as possible and then hung 

 perfectly level by the supporting vertical 

 cables, which should be spaced about 1 ft. 

 apart. When all vertical cables are se- 

 cured to both the upper and lower cords 

 the latter is drawn up again and secured 

 at each end. 



Planks are laid across the lower cord 

 and held in place by driving large staples 

 over the rope and into the bottom of the 

 plank. The tables should be studied 

 closely. Table 2 gives the size of the post, 

 length above and below ground and size 

 of spread footing, while Table 3 gives the 

 size of the ropes to use for the various 

 lengths of the span. In the last column 



of this table is given the size of the bottom 

 cord of round iron bar, which is used in 

 place of manila rope, and in Table 4 is 

 given the number and size of the bars 

 necessary to reinforce the columns shown 

 or mentioned in Table 2. 



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ELECTRIC LIGHT- 



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■r^y FIG 3 



A cross section of the completed bridge and 

 the detail of the anchor post and its base 



The illustration. Fig. 2, gives a cross- 

 section of the completed bridge, while 

 Fig. 3 shows a little more detail of the 



