Ch loride of Li me. 371 



preference only on the circumference, so that in very weak 

 solutions the middle remains unchanged, and the action is 

 only shewn on the borders. 



It should be remarked, that the solution of chloride of 

 lime should not be brought upon the dyed cotton before it 

 has become clear, which soon takes place. In no case 

 should it be filtered, as it weakens the chloride of lime, 

 and destroys the filtering-paper. 



If a piece of calico is moistened with a clear solution of 

 chloride of lime, and hung up in a room, a strong odour of 

 chlorine will soon be perceived, and the calico in a short 

 time becomes brittle, and can be torn to pieces. 



The same destructive effect is produced by the chloride of 

 lime upon calico which is allowed to remain for some time 

 in a solution of chloride of lime. 



A clear solution of chloride of lime acts more injuriously 

 upon cotton than one which is milky, and contains an ex- 

 cess of lime. Hence, the clear solution of the chloride of 

 lime destroys colours, which the milky solution leaves un- 

 altered. 



This property is important in the manufacture of madder- 

 purple, where the solution of chloride of lime is employed 

 to prepare on the purple, white, blue and yellow, &c, pat- 

 terns. The madder-purple is printed with mordants, which 

 decompose the chloride of lime, and set the chlorine free, 

 which bleaches during its disengagement. On the other 

 hand, the unprinted portions retain their red colour, un- 

 less when the solution of chloride of lime contains no excess 

 of lime. The lime is also useful by saturating the chlorine 

 set at liberty. In the opposite case, instead of a regular 

 edged pattern, the borders will be irregular. 



It has been already stated, under the tests for chloride of 

 lime, that it bleaches many colours when locally applied. 

 The following solution may be employed for printing it on 

 cloth : — 1 lb. chloride of lime in 30 to 40 lbs water. It is 

 very difficult, however, to thicken such a solution. 



To dissolve the chloride of lime, much water must not be 

 at once poured upon it. It should first be mixed into a 

 magma, with double its weight of water; the large pieces 

 should be broken by means of a wooden pestle, and allowed 



2 b2 



