238 
Same mordant, weft threads, 6 experiments... 2201 grs. 
Same weft threads in the unmordanted parts, 
6 experiments 2906 grs. 
The above experiments show a decided diminution of 
strength in those threads which had received the mordant. 
The unmordanted threads had, of course, been submitted to 
the same acid and other treatments. 
A repetition of these experiments upon another piece of 
cloth of different origin but similarly printed, and which had 
been dyed in madder and then treated with hydrochloric 
acid, gave the following results : — 
Alumina mordant for red, warp threads, 10 
experiments 1906 grs. 
Unmordanted threads, contiguous, 10 experi- 
ments 2061 grs. 
showing a diminution of strength. ^ 
Iron mordant for black, warp threads, 10 
experiments 1631 grs. 
TJnmordanted threads, contiguous, 10 expe- 
riments 2260 grs. 
showing a considerable diminution of strength. 
Experiments on cotton hairs, taken from mordanted and 
unmordanted threads , which had been treated by acid. 
Alumina mordant for red, 8 experiments ...... 603 grs. 
Not mordanted adjacent hairs, 5 experiments. 71*6 grs. 
The uncertainty as to whether the mordant had actually 
touched the hairs in the centre of the threads caused these 
experiments to be discontinued and the following instituted. 
Cotton m ordanted in the wool. Small parcels of N cw ( Irleans 
cotton were steeped separately in ordinary iron liquor (crude 
pyrolignate of iron) and red liquor (crude acetate of alumina), 
