756 SCOURING 



facturiiig the same pigment. Its preparation is very simple, but its formation is 

 accompanied "with some interesting circumstances. On mixing equal parts of acetate 

 of copper and arsenious acid, each in a boiling concentrated solution, a bulky olive- 

 green precipitate is immediately produced ; while much acetic acid is set free. The 

 powder thus obtained appears to be a compound of arsenious acid and oxide of copper, 

 in a peculiar state; since when decomposed by sulphuric acid, no acetic odour is 

 exhaled. Its colour is not changed by drying, by exposure to air, or by being heated 

 in water. But, if it be boiled in the acidulous liquor from which it was precipitated, 

 it soon changes its colour, as well as its state of aggregation, and forms a new deposit 

 in the form of a dense granular beautiful green powder. As fine a colour is produced 

 by ebullition during five or six minutes as is obtained at the end of several nours by 

 mixing the two boiling solutions, and allowing the whole to cool together. In the 

 latter case, the precipitate, which is slight and flocky at first, becomes denser by 

 degrees ; it next betrays green spots, which progressively increase, till the mass grows 

 altogether of a crystalline constitution, and of a still more beautiful tint than if formed 

 by ebullition. 



When cold water is added to the mixed solutions immediately after the precipitate 

 takes place, the development of the colour is retarded, with the effect of making it 

 much finer. The best mode of procedure is to add to the blended solutions their 

 own bulk of cold water, and to fill a globe up to the neck with the mixture, in order 

 to prevent the formation on any such pellicle on the surface as might, by falling to the 

 bottom, excite premature crystallisation. Thus the reaction continues during two or 

 three days with the happiest effect. 



SCOURING. This art is that which is employed for removing grease spots, &c., 

 from cloths and furniture, which require skill beyond that of the laundry. It is 

 divided into two distinct branches, viz. French and English cleaning. We will first 

 give an outline of English cleaning. 



Gentlemen's clothes, such as trowsers, coats, &c., are treated in the following 

 manner. They are stretched on a board, and the spots of grease, &c,, first taken out 

 by rubbing the spots well with a brush and cold strong soap-liquor; they are then done 

 all over with the same, but the grease spots are done first, because they require more 

 rubbing, of course, than the other parts, and when all the substance is wet the spots 

 will not be so easily distinguished. After treatment with the strong soap-liquor, the 

 soap is worked by a weaker soap-liquor ; the articles are then well washed off with 

 warm water, and treated with ammonia (if black), solution of common salt, or dilute 

 acid, according to circumstances. They are then drained, beaten out with a little size, 

 pressed and dried. 



Ladies' articles of dress, as shawls and woollen dresses. The spots are first removed 

 by rubbing them on the board with very strong soap-liquor ; they are then put into 

 a strong soap-liquor, and well worked about in it ; then taken out and treated with 

 a weaker soap-liquor, to work out the soap, &c. ; rinsed with warm and cold water 

 alternately ; treated with solution of common salt or very weak acid, to maintain the 

 colours. They are starched, if necessary, and ironed. Woollen dresses that are taken 

 to pieces are calendered instead of ironing. 



Silk dresses, $c., are always taken to pieces, and each piece done separately, and 

 as quickly as possible. If there are any spots of grease, they are taken out first, as 

 above mentioned. Each piece, after the spots are removed, is immediately placed in 

 a strong soap-liquor, and well worked about in it, and then into a thinner soap-liquor ; 

 well washed out with cold water, and treated with solution of common salt, or very 

 weak acid, or both, as required ; each piece is then neatly folded and wrung separately, 

 again folded smoothly and placed in dry sheets, and pressed, so as to remove all 

 dampness from them ; they are then put into a frame, a little size or sugar-and- 

 water being used to stiffen and glaze ; lastly, they are dried while on the frame by a 

 charcoal fire. 



Furniture, as curtains, $c. These things are put into a tub, with a strong cold 

 soap-liquor, and well punched about with a large wooden punch made on purpose; and 

 a great deal depends upon this being properly done. They are then treated in the 

 same manner in a weaker soap-liquor, well rinsed with water, treated with common 

 salt or weak acid, as required, wrung out, and dried. Woollen furniture will generally 

 require to be treated several times with the first strong soap-liquor, to remove the 

 dirt, but for cotton furniture once will be generally sufficient. 



Carpets. These are well beaten, then laid down on the floor of the dye-house, and 

 well scrubbed with strong cold soap-liquor, by means of a long-handled brush or 

 broom ; then treated with a weaker soap-liquor ; well rinsed with water, by throwing 

 pails of water over them, and still rubbing with the brush ; treated with water, to 

 which a very small quantity of sulphuric acid has been added, to retain the colours- 

 rinsed again, hung up to drain, and then hung up in a warm room to dry. 



