140 Laboratory Arts 



Stains for Woodwork. i. Mahogany stain is made by 

 dissolving a small quantity of Bismarck brown (aniline dye) in 

 rectified spirit, and pouring the solution into warm water. The 

 strength of solution may be varied to suit varying require- 

 ments. 



2. Walnut stain is made by mixing a quantity of Vandyke 

 brown (ground in water) in a mortar, with strong ammonia 

 solution, pouring off the resulting solution into a well-stoppered 

 Winchester quart bottle and repeating the addition of ammonia 

 solution and the stirring until all the solid disappears. The 

 solution so obtained is suitably diluted with water, and shaken. 



3. Permanganate of potash dissolved in water produces a 

 walnut-coloured stain on wood, but owing to the action of the 

 acids in the wood the colour is fleeting. 



4. Bichromate of potash solution stains oak a dark brown, 

 and is used in producing " fumed oak." A dilute solution of 

 ammonia has much the same effect, but this is not permanent, 

 though, curiously enough, the stain upon oak produced by 

 shutting it up in an airtight box containing also a saucer of 

 o'88o ammonia solution, is permanent; oak may be darkened 

 to blackness by this treatment. 



5. Green oak or ash may be produced by treatment with 

 solutions in water of various aniline colours ; in each case the 

 colour must first be made up in rectified spirit, and added to 

 water. " Aniline green," " seal brown," " diamine yellow," 

 judiciously mixed, will produce a pleasing colour free from the 

 crudeness frequently shown by " stained green " furniture. 



6. A stain for the imitation of pitch pine may be made up 

 by mixing a little burnt umber with yellow ochre, in turpen- 

 tine and raw linseed oil, while without the burnt umber an 

 imitation of yellow pine is obtained. 



It will be noticed that in each case, save No. 6, water 

 stains are recommended. Spirit stains are very deceptive, 

 difficult to apply, and produce unsatisfactory results. They 

 rub off when dry, and dry many shades darker than they 

 appear while being applied, consequently the greatest dis- 

 appointment frequently results from their use. It is almost 

 impossible to French polish satisfactorily over a spirit stain. 



