TESTS OF THE STRENGTH OF SILK FIBRES. TL 
rupture is expressed in millimeters in a length of twenty millimeters of 
fibre, as well as in per cents. No special experiments were made to 
dletermine the limits of elasticity, and though the stretch will vary 
somewhat with the length of fibre held between the clamps of the in- 
strument, limiting thus the character of the results, yet for the purpose 
of comparison the figures we have given will prove amply sufficient, 
and they will clearly show the differences in the quality and value of 
the samples submitted to examination. 
Other qualities of the fibre and the cocoons have suggested them- 
selves for investigation in the course of this work, but their examina- 
tion has been precluded by the limited time at our disposal for the 
present study of this staple. We, therefore, submit these results in the 
hope that they may serve the ends desired. 
