WOOL. 209 



accounted for by the wool having been only imperfectly washed or 

 scoured. 



Perhaps one of the oldest and well-known scouring agents is stale 

 urine or "lant," which was formerly collected in the woollen districts. 

 Owing to its value as a scouring agent it serves as a good wool cleanser,, 

 and renders the fibres sjoft and elastic, while their physical structure 

 remains normal. The disagreeable odour of stale larit has caused other 

 detergents to be used, such as ammonium carbonate, potash and soda 

 soap. 



The most suitable temperature for the scouring solution must depend 

 upon the character of the various wools used, and the amount of dirt 

 they contain. It is a good plan to test the temperature and the 

 alkalinity of the bath by putting in a few samples, and then noting if the 

 dirt or grease is persistent while immersed in the solution. If the bath 

 is found suitable, a larger quantity may at once be submitted to the bath 

 already formed. 



^Drying. After the wool has been thoroughly washed, it requires to 

 be dried as quickly as possible. A well-known process is to have the 

 wool laid upon wire cages, and while in this position to pass hot air over 

 it; this has the necessary drying effect upon the material. It is 

 important that the drying should be done as evenly as possible ; if done 

 unevenly, it may cause the wool to become scorched. Another method 

 of employing hot air is to use a machine in which the wool is fed and 

 caused to travel over drying shelves or tables being afterwards delivered 

 in a dry condition. 



Wool Willowing. This process has an effect upon the wool fibres 

 similar to that which the opening machine has upon cotton fibres. In 

 some cases it becomes necessary to mix wool and cotton together in the 

 willow opener. 



Fig. 136 shows wool and cotton fibres taken from the willow after 

 having undergone treatment in the machine. The wool fibres show an 

 entanglement and rolled-up character, while the cotton displays a want of 

 curliness, but aggregates into tufts, showing a whiteness that is peculiar 

 to these fibres. The willowing machine was formerly used extensively for 

 the cleaning of cotton, but has latterly been discarded, and the separat- 

 ing and disentanglement of woollen fibres is spoken of as Teazing. The 

 cylinder of the machine which effects this is run at 500 revolutions per 

 minute, and the working rollers which take and separate the felted fibres 

 from the cylinder are run at B, slower rate. By this method the fibres 

 are thoroughly separated, and rendered pliable and flexible for the process 

 of scribbling. " Willowing" is synonymous with " Teazing." 



Wool Carding.. The object to be attained in wool carding differs 



14 



