SQ4 INKS. 



arabic. For example, a strong decoction of Brazil wood, with at 

 much alum as it can dissolve, and a little gum, forms a good red 

 ink. These processes consist in forming a lake, and retarding its 

 precipitation by the gum. 



On many occasions it is of importance to employ an ink inde- 

 structible by any process, that will not equally destroy the material 

 on which it is applied. Mr. Close has recommended for this pur. 

 pose 25 grains of copal in powder dissolved in 200 grains of oil of 

 lavender, by the assistance of gentle heat, and then mixed with 2', 

 grains of lamp black, and half a grain of indigo : or 120 grains of 

 oil of lavender, 17 grains of copal, and 60 graius of vermilion. A 

 little oil of lavender, or of turpentine, may be added, if the ink be 

 found too thick. Mr. Sheldrake suggests, that a mixture of genu- 

 ine asphaltum dissolved in oil of turpentine, amber, varnish, and 

 lamp black, would be still superior. 



When writing with common ink has been effaced by means of 

 oxygenized muriatic acid, the vapour of sulphuret of ammonia, or 

 immersion impregnated with this sulphuret, will render it again 

 legible, Or if the paper that contained the writing bo put into a 

 weak solution of prussiate of potash, and when it is thoroughly wet 

 a sulphuric acid be added to the liquor, so as to render it slightly 

 acidulous, the same purpose will be answered. 



Golden INK. As writing, before the invention of printing, 

 was the only method of transmitting to posterity the works and 

 discoveries of celebrated men, it became in the fourteenth and 

 fifteenth centuries an art much cultivated, and in which many per- 

 sons excelled. The manuscripts of those periods contain writing, 

 the neatness and regularity of which are astonishing. Transcribers 

 were even acquainted with a method of ornamenting the initial 

 letters with gold, which they applied in such a manner as to pre. 

 serve all its splendour. Writing, by the invention of printing, 

 having become of less importance, soon degenerated, and the secret 

 of applying ;;old to paper and parchment, like many other arts, was 

 at length lost. The Benedictines however, rediscovered this secret, 

 and specimens of the process, and parchment containing writing in 

 gold letters, as brilliant as those so much admired in the ancient 

 manuscripts, have been seen at the Abbey Saint.Gcrmaiiudes-Pres, 

 at Paris. This process may be exceedingly useful, and may fur- 

 ther hints for improving some of the other arts, which are all con- 

 nected, and mutually tend to promote each other. 



