328 



DICKSON ON THE VALUE OF HIS PATENT 



taken from the field, without any retting or liquid process, but 

 prepared by Mr. Dickson's patent machines. 



42 J fathoms of No. 25 rope yarn, weighing 15§oz., 



was subjected, before breaking, to a strain of . 172lbs. 

 Ditto ditto ditto 178 „ 



Ditto ditto ditto 162 „ 



In three several trials of strength . . . 512 „ 



Average breaking strain . . 170 „ 



Petersburgh hemp, retted as usual, and spun into No. 25 

 yarn for rope. 



42J fathoms of No. 25 rope yarn, weighing lOJoz., 

 had three several trials under the same circum- 



stances, and broke at a strain of 138lbs. 



Ditto ditto ditto 139 ,, 



Ditto ditto ditto 116 ,, 



In three several trials of strength . . . 393 



Average breaking strain . . 131 ,, 



Mr. Dickson's Italian hemp, being perfectly free from 

 wood, resin, or dust, it spun up hard, level, and close ; and, 

 although not heckled, the authorities thought it equal in 

 weight to No. 20 rope yarn spun from their Russian hemp ; 

 and Mr. Dickson having proposed that his Italian green hemp, 

 No. 25 yarn, should be placed in competition with the 

 Eussian hemp, No. 20 rope yarn (an article largely used in 

 the manufacture of rope in the dockyards) with one-fifth 

 more in weight than No. 25. The result of the latter experi- 

 ment was as follows : — 



No. 20 rope yarn, No. 1 strain, broke . 139lbs. 

 J? 55 » 2 ,, . 119 ,, 



5, 5 5 3 j, „ . . 145 ,, 



403 „ 



