576 Philippine Journal of Science 1919 
Table IV. — Ropes made of Philippine fibers arrayiged in order of mean- 
tensile strength when wet, etc. — Continued. 
ROPES MADE OF MISCELLANEOUS FIBERS. 
Fiber. 
Mean wet tensile 
strength. 
No. 
Per sq, 
cm. 
Per sq. 
inch. 
Kilos. 
Lhs. 
1 
Musa textilis; grade "G” abaca; rope, 16 mm. in circumference » _ 
1, 180 
16,700 
2 
Musa textilis; grade “F” abaca; rope, 31 mm. in circumference “ 
946 
13, 600 
3 
Musa textilis; grade “F” abacd; rope, 15 mm. in circumference® 
923 
13, 100 
4 
Musa textilis; ?rade “G” abacd; rope, 26 mm. in circumferences 
759 
10,800 
5 
Agave cantata; maguey; grade, Cebu No. 2“ 
651 
9, 220 
6 
325 
4 
7 
Cori/p/iaeZaia; buntal; vascular libers in petioles . 
257 
3, 650 
8 
Dendroealamus merrillianus^ 
179 
2, 640 
9 
Cocos nucifera; rope, 24 mm. in circumference c 
148 
2, 100 
10 
Cocoa «wc?ycra; rope, 44 mm. in circumference^ .. _ 
146 
2,070 
11 
Cocos nucifera; rope, 50 mm. in circumferencee 
136 
1 , 9S0 
12 
Anamirta cocculust 
1 no 
1,670 
480 
6,816 
> Machine-made rope ; all other ropes are handmade. 
>> This rope has two strands only ; all other ropes have three strands. 
' Immersed in stagnant tap water twenty-one days before testing ; all other ropes were 
steeped in tap water only twenty-four hours before being tested. Rope made of fiber that 
had been machine cleaned at the Bureau of Science from Laguna husks. 
** Rope made of fiber that had been machine cleaned at the Bureau of Science from Laguna 
husks. 
' Rope made at Caoayan, Ilocos Sur, from salt-water retted coir. 
' Three-strand rope made of the entire stem of the vine. 
rarely in three; this shows that the various strands are not 
equally taut in manufacture, and that the intensity of stress is 
greater in some fibers than in others. 
As a substitute for stresses calculated on the basis of sectional 
areas of cordage and similar material (paper, leather, etc.), 
the computation of whose solid sectional area presents diffi- 
culties, Keuleaux in 1861, and Rankine in 1866, intro- 
duced the concept of breaking length. The breaking length of 
a rope is that length which when suspended at one end will 
cause the specimen to break of its own weight. It is com- 
puted by dividing the breaking load or tensile strength in 
pounds or kilograms by the weight in pounds per foot or in 
kilograms per meter, respectively, as follows: 
Breaking load 
= Breaking length. 
Weight per unit length 
“ Heermann, Paul, Mechanisch- und Physikalisch-technische Textile- 
Untersuchung. Julius Springer, Berlin (1912) 160-161. 
