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strength may be explained by the complete bedding of the 
cotton hairs, so forming a more compact thread. At any 
rate, it seems proved that the strength of cotton is not injured 
by the ordinary process of bleaching for printing. 
Effect of printing , dyeing, soaping , 8fc. A portion of S.V. 
was printed, dyed, and finished as a first-class madder purple, 
and 20 experiments made upon the warp and weft threads. 
with the following results : — 
Strength of printed and finished warp 3569 
Ditto of printed and finished weft 2669 
Here it is seen the warp threads have gained more than 
they lost in bleaching, while the weft threads have lost 
something. The increase of strength in the warp threads is 
partly, if not wholly explained by the diminution of length, 
the two yards gained in bleaching, and rather more, being 
absorbed in the processes of dyeing, soaping, &c., and the 
thread consequently becomes thicker and stronger. 
Mordanted cloth treated with acid. These experiments 
are interesting, as touching upon the chemical versus the 
physical theory of dyeing. A piece of calico was chosen 
printed by blocks in wide longitudinal stripes, with the usual 
mordants for madder or garancine dyeing ; it was aged, 
cleared, &c., as usual, to remove all loose mordant. Portions 
containing mprdanted and unmordanted parts were treated 
by hydrochloric acid to remove the mordants, then carefully 
washed, and the strength of the threads tested. The results 
are as follow : — 
Iron mordant for black, warp threads, 10 
experiments 3450 grs. 
Warp threads contiguous to the mordanted 
threads, 10 experiments 3715 grs. 
